Step-by-step explanation:
I never learned this (for good reasons, I say). for me this is the strangest thing in math. math is precise. we are not guessing around when we can actually calculate things.
this is definitely ok, when just trying to decide, if one fraction is larger than the other, but to use that for an actual operation among fractions, is the biggest nonsense I have ever seen in math lessons (and not simpler than doing the precise calculation). again, math is a precise thing. the only valid level of imprecise answers is rounding, but only for the end result, not for intermediate results, because the rounding errors are rarely compensating for each other, they mostly pile up making the end result even less precise.
enough with the venting ...
benchmark fractions are the simple fractions (and their multiples)
1 (=1/1), 1/2, 1/3, 1/4, 1/5, 1/6
and then in steps of 2 :
1/8, 1/10, 1/12, ...
we try to find the closest simple fractions to our actual fractions and use them to estimate the actual result.
the simplest (but also normally the least precise) benchmark approach is using 1/2 as benchmark unit and 0, 1/2, 1 as benchmarks.
so, is 10/12 closest to 0, to 1/2 or to 1 ?
we know that 0 in 12ths would be 0/12, 1/2 would be 6/12, and 1 would be 12/12.
so, out of these 3 values 10/12 is closest to 12/12 (=1), so that is what you are choosing as representation.
is 3/8 closest to 0, 1/2 or to 1 ?
we would have 0/8, 4/8, 8/8.
and 3/8 is closest to 4/8 (= 1/2), and that is what we are choosing here as representation.
and the estimated result of 10/12 - 3/8 = 1 - 1/2 = 1/2 or 4/8 or 6/12.
let's pick 1/4 as benchmark unit.
so, are the numbers closest to
0, 1/4, 2/4, 3/4 or 1 (4/4) ?
for 10/12 we get then
0/12, 3/12, 6/12, 9/12, 12/12
and 10/12 is closest to 9/12 (3/4), which we pick as representation.
for 3/8 we get
0/8, 2/8, 4/8, 6/8, 8/8
if equidistant, we have to round up, so, we get 4/8 (2/4), which we pick as representation.
and the estimated calculation is
10/12 - 3/8 = 3/4 - 2/4 = 1/4
which is really horrible ...
2 and 4 are factors of 12 and 8. all smaller benchmark fractions (<1/4; so, e.g. 1/5, 1/6, 1/8. ...) are not meeting that criteria, making the benchmark finding much harder. so, I would not try that.
the real result is
the LCM of 12 and 8 is 24 (2×12 and 3×8).
so, we have
20/24 - 9/24 = 11/24 (almost 1/2).
so, actually, the benchmark unit of 1/2 is giving the best result here.
but to just do the exercise of benchmark units that are not factors of both denominators, let's pick 1/6
so, are the numbers closest to
0, 1/6, 2/6, 3/6, 4/6, 5/6 or 1 (6/6) ?
for 10/12 we get (all nicely)
0/12, 2/12, 4/12, 6/12, 8/12, 10/12, 12/12
so, 10/12 is closest to 10/12 (of course) = 5/6, which we pick as representation.
for 3/8 we get (ugh, we have to go for 24ths here too as 4×6 and 3×8)
0/24, 4/24, 8/24, 12/24, 16/24, 20/24. 24/24
3/8 = 9/24
so, the closest number to 9/24 is 8/24 (= 2/6), which we pick as representation.
and the estimated calculation is
10/12 - 3/8 = 5/6 - 2/6 = 3/6 = 1/2
did I say already that I don't like this ? that I don't see the advantage to the actual calculation ?
so, just in case : I don't like this (ugh) !
-2x+4y=28
-3x +2y = 6
Solve for x
Answer:
x=4, y=9
Step-by-step explanation:
Solve with substitution.
Which expression is equivalent
Answer:
it should be A i think
Step-by-step explanation:
i used a calculator
what expression is equivalent to 1/4 (x+24)
Use the Distributive Property, which states the following:-
[tex]\sf{a(b+c)=ab+ac}[/tex]
Where
we distribute a by multiplying it times b and c
a, b, and c can be either constants (numbers) or variables (letters)
Distribute:-
[tex]\sf{\displaystyle\frac{1}{4}(x+24)}}[/tex]
Multiply the term before the parentheses by the terms inside the parentheses:-
[tex]\sf{\displaystyle\frac{1}{4} x+6}}[/tex]
note:-Hope everything is clear; if you need any explanation/clarification, kindly let me know, and I will comment and/or edit my answer :)
Find the area of each circle with the given radius or diameter. Use 3.14 for pi.
Answer: (Note*: Radius is half of the diameter, so the d = 2 and d = 12 have been converted into radius's instead to solve the problem).
r^2 = 4 in: 50.24 in^2.
r^2 = 2 in: 12.56 in^2.
d = 2 or r^2 = 1 in: 3.14 in^2.
r^2 = 8 in: 200.96 in^2.
d = 12 or r^2 = 6 in: 113.04 in^2.
Step-by-step explanation: To find the area of a circle, you need the radius squared times pi, which is 3.14. The following is solved below:
4^2 x 3.14 = 50.24 in^2.
2^2 x 3.14 = 12.56 in^2.
1^2 x 3.14 = 3.14 in^2.
8^2 x 3.14 = 200.96 in^2.
6^2 x 3.14 = 113.04 in^2.
Therefore, the following above are the answers you need.
Let me know if this is right! :)
Answer:
r = 4.) 50.24
r = 2.) 12.56
d = 2.) 3.14
r = 8.) 200.96
d = 12.) 113.04
Step-by-step explanation:
The formula for finding the area of a circle would be π(pi) x r (radius)²
1.) r = 4
4 x 4 = 16
16 x 3.14 = 50.24
2.) r = 2
2 x 2 = 4
4 x 3.14 = 12.56
3.) d = 2
2 ÷ 2 = 1
1 x 1 = 1
1 x 3.14 = 3.14
4.) r = 8
8 x 8 = 64
64 x 3.14 = 200.96
5.) d = 12
12 ÷ 2 = 6
6 x 6 = 36
36 x 3.14 = 113.04
-kiniwih426
determine how many ways a president, vice president and treasurer can be chosen from a math club that has 7 members.
Answer:
210
Step-by-step explanation:
There are 7 choices for president.
Then there are 6 choices for vice-president.
Finally, there are 5 choices for treasurer.
7 × 6 × 5 = 210
Mrs. smith has $1500 in a retirement account earning 5% interest. each year she makes an additional deposit of $500 to her account. after 3 years, what would her account balance be?
Answer:
$3,312.69
Step-by-step explanation:
What she started with: $1500
Year 1: 1500 + 1500(.05) + 500 = $2,075
Year 2: (2.075)1.05 + 500 = $2,678.75
Year 3: (2678.75)1.05 + 500 = $3,312.69
can someone help me.
Step-by-step explanation:
side of square = 10
area of square = side² = 10² = 100 cm²
P.S : ARE YOU SURE THE OPTIONS ARE CORRECT ???
heeeeeeeeeeelllllllllppppppppppppp
Answer:
88
Step-by-step explanation:
The area of a triangle is calculated using the following formula:
1/2*b*h (b: base, h: height)
The height here is 11 and the base is 16
1/2*16*11 = 88 units square
Choose the polynomial written in standard form. x2 4x4 10x6 x4 4x3 10x x7 4x3 10x4 x6 4x3 10x7
The polynomial that is written in standard form out of the given options is given by: Option 2: x^4 + 4x^3 + 10x
What is standard form of a polynomial?Suppose the considered polynomial is of only one variable.
Then, the standard form of that polynomial is the one in which the terms with higher exponents are written on left side to those which have lower exponents.
What are terms in polynomials?Terms are added or subtracted to make a polynomial. They're composed of variables and constants all in multiplication.
Example:
[tex]x^3 + 3x +5[/tex]
is a polynomial consisting 3 terms as [tex]x^3, 3x \: \rm and \: 5[/tex]
Cheking all the options for them being in standard form or not:
Option 1: [tex]x^2 + 4x^4 + 10x^6[/tex]Second term has 4 as exponent, but on its left, the first term has 2 as exponent. So higher expoent holding term is not on left. Thus, this polynomial is not in standard form.
Option 2: [tex]x^4 + 4x^3 + 10x[/tex]4 > 3 > 1 (comparing the exponents), and the terms holding them are also in this order (left to right).
Thus, this polynomial is in standard form.
Option 3: [tex]x^7 + 4x^3 + 10x^4[/tex]Not in standard form because the last term has bigger power then the term on its left.
Option 4: [tex]x^6 + 4x^3 + 10x^7[/tex]Not in standard form because the last term has bigger power then the term on its left.
Thus, the polynomial that is written in standard form out of the given options is given by: Option 2: x^4 + 4x^3 + 10x
Learn more about standard form of a polynomial here:
https://brainly.com/question/15313798
your older sister tells you that you seem to be short for your age. in school, your teacher measured your height and that of your classmates to compute for your BMI. you teacher tells you that your height belongs to the 9th decile in the class. assuming you and your classmates have similar ages, would you agree with what your sister says? why?
Answer:
No.
Step-by-step explanation:
No, because the 9th decitile is equal to the 90th decitile, and so that means that you're tall.
Which of these pairs are like terms?
20 x, 0.8 x
17, 3 x
14 x, 14 x2
0.5 x, 0.5 y
The pair of algebraic expressions which are like terms is; 20x and 0.8x.
What are like terms?Algebraic expressions are pronounced as like terms if the terms contain the same variable raised to the same exponent.
check all options:
20x, 0.8x
same variable and exponent
17, 3x
Not same variable
14x, 14x²
Same variable, not same exponent
0.5x, 0.5y
Not same variable
On this note, it follows that the terms 20x and 0.8x are like terms.
Read more on like terms;
https://brainly.com/question/480769
1. Find the surface area of the square pyramid. 13 m 14 m
Answer: [tex]560m^2[/tex]
Step-by-step explanation:
First begin by finding the surface area of the base, which is simply length * width. In this case,
[tex]14*14 = 196 m^2[/tex]
Next, find the surface area of one of the sides of the pyramid. This formula for this is:
[tex]\frac{1}{2}*base*height[/tex]
Since we know the height to be 13 meters and the base to be 14 meters, we can solve for one side.
[tex]\frac{1}{2}*14*13 = 91 m^2[/tex]
We multiply this by 4 to give us all 4 sides of the pyramid:
[tex]91m^2 * 4 = 364m^2[/tex]
Adding together the surface area of the sides and the base gives us:
[tex]196m^2 + 364m^2=560m^2[/tex]
The radius of a circle is 16 cm. Find its area in terms of pi
Can someone help me?
Answer:
What are you trying to do you have not Explained to us
Step-by-step explanation:
In the figure shown, what is the measure of angle x?
Triangle ABC has measure of angle BAC equal to 40 degrees and the measure of angle ABC is equal to 70 degrees. The side BC of the triangle is extended till D. The angle ACD is labeled as x.
100 degrees
110 degrees
120 degrees
140 degrees
➾Firstly, we will find the measure of [tex]\angle[/tex]ACB.
We know that,
Sum of all interior angles of a triangle = 180°.
[tex]\rightarrow[/tex][tex]\angle[/tex]BAC + [tex]\angle[/tex]ABC + [tex]\angle[/tex]ACB = 180°
[tex]\rightarrow[/tex] 40°+70°+[tex]\angle[/tex]ACB = 180°
[tex]\rightarrow[/tex] 110°+[tex]\angle[/tex]ACB = 180°
[tex]\rightarrow[/tex] [tex]\angle[/tex]ACB = 180°-110°
[tex]\rightarrow[/tex][tex]\angle[/tex]ACB = 70°
So, the measure of [tex]\angle[/tex]ACB = 70°.
➾ Side BC of the triangle is extended till D. So, we have to find the measure of [tex]\angle[/tex] ACD.
As we know that,
Sum of any two or more angles that lie on a straight line = 180°.
So, [tex]\sf\angle{ACB}[/tex]+[tex]\sf\angle{ACD}[/tex] = 180°
[tex]\rightarrow[/tex] 70° + [tex]\sf\angle{ACD}[/tex] = 180°
[tex]\rightarrow[/tex][tex]\sf\angle{ACD}[/tex] = 180°-70°
[tex]\rightarrow[/tex][tex]\sf\angle{ACD}[/tex] = 110°.
Therefore, measure of [tex]\sf\angle{ACD}[/tex] = 110°.
____________________________
Hope it helps you:)
help :(
“two less than a number is less than or equal to thirty three”
- The inequality translated in numerical form
- The solution in set notation
- The solution in interval notation
Answer:
- The inequality translated in numerical form
Step-by-step explanation:
PLEASE HELP TAKING TEST RN what are the midline, amplitude, period of this function?
Answer:
midine y=2
amplitude -3
period 5pie
is (1,9) included in the graph p=3m+6
As the planets revolve around the Sun, sometimes Earth is between the Sun and Mars (Point A) and sometimes the Sun is between Earth and Mars (Point B). The distance from the Sun to Mars is approximately 2.3 times 10 Superscript 8 km, and the distance from the Sun to Earth is approximately 1.5 times 10 Superscript 8 km.
The rotations of Earth and Mars around the sun.
Which statements are true? Check all that apply.
Answer:
ummmm i think its B and D
Step-by-step explanation:
Simplify this exponential expression:
(-49) 2/5
Answer:
I think it is 12 4/5
Step-by-step explanation:
hope this helps if not let me now
B
An athlete ran uphill at 3 metres per second for x seconds , downhill
at 6 metres per second for y seconds and covered a total distance
of 375 metres . If the athlete took 5 seconds longer to run uphill than
downhill, calculate the values of xandy.
(5)
Step-by-step explanation:
- The distance traveled to get to the top of the hill will be equal to the distance traveled to get to the bottom of the hill. Distance down the hill = Distance up the hill = 187.5 meters.
- Only the speed of going up the hill and down the hill will be different.
11) Ryan and three friends went to Fridays the bill was $123,42 If they gave an 18 percent tip, how much did they have to pay if they divided the total bill equally?
PART A
Mrs. Jackson is planning an outdoor barbeque. She will cook 2 ears of corn per person plus two extra. If 16 people plan to come, how many ears of corn will Mrs. Jackson cook?
Answer:
34
Step-by-step explanation:
2 x 16 + 2
_________
2 x 16 = 32
_________
32 + 2 = 34
Answer:
30 or 64
Step-by-step explanation:
30 Because... 2 corns for every one till they rech 15..
that's mean (2 x 15)
64 Because... 2 corns plus 2 extra if they rech 16....
that's mean (4x16)
i need help 9th grade math
Answer:
g(x) = 4x + 5
Step-by-step explanation:
f(x) + g(x) = 10x + 7 , then
6x + 2 + g(x) = 10x + 7 ← subtract 6x + 2 from both sides
g(x) = 10x + 7 - 6x - 2 ← collect like terms
g(x) = 4x + 5
Let's find
(f+g)(x)=f(x)+g(x)10x+7=6x+2+g(x)g(x)=10x-6x+7-2g(x)=4x+5Option D
PLEASE HELP. WILL GIVE BRAINLIEST !! Find the cross product <-1, -3, -8> x <7,4, -5>. Is the resulting vector perpendicular to the given vectors?
<47, -61, 71>; yes
<41, -59, 77>; no
<-59, 71, 41>; yes
<41, -61, -59>; no
Answer:
Answer:
The cross product is 47 i - 61 j + 17 k.
Step-by-step explanation:
Given that-
a = < -1, -3, -8 > , b = < 7, 4, -5 >
The cross product is
a × b =\begin{gathered}\left[\begin{array}{ccc}i&j&k\\-1&-3&-8\\7&4&-5\end{array}\right]\end{gathered}⎣⎢⎡i−17j−34k−8−5⎦⎥⎤
= i ( - 3 × -5 - 4 × -8 ) - j ( -1 × -5 - (-8) × 7 ) + k ( -1 × 4 - 7 × -3 )
= i ( 15 + 32 ) -j ×( 5 + 56 ) + k ( -4 + 21 )
= i ( 47) - j (61 ) + k (17)
= 47 i -61 j + 17 k
As we know that if two vectors A & B are perpendicular then
A . B = 0
So here only the given vector b = < 7,4, -5> is perpendicular to the resulting vector .
Step-by-step explanation:
47, -61, 71>; yes
What is the surface area? 34 in 30 in 34 in 32 in 36 in
Answer:
If I am correct to work out the surface area you need to do base times height so the calculation would be...
32(base) × 30(height)
which equals 960 square inches
Please do check with someone else the answer, as I am not that confident and new
How many groups of tens would represent the value of the digit 4 in the number 14752?
A. 4
B. 40
C. 400
D. 4000
show me why
Answer:
C. 400
Step-by-step explanation:
The number 14752 is "Fourteen thousand, seven hundred and fifty two"
The 1 is the place of ten thousands ⇒ 10,000
The 4 is the place of thousands ⇒ 4,000
The 7 is the place of hundreds ⇒ 700
The 5 is the place of tens ⇒ 50
The 2 is the place of units ⇒ 2
So we need to find how many groups of tens are in 4000.
To do this, divide 4000 by 10.
To divide anything by 10, simply move the decimal point one place to the left.
Therefore, there are 400 groups of ten in 4000
as 400 × 10 = 4000
Find x to the nearest tenth
Answer:
[tex] {x}^{2} = {8.6}^{2} + {11.5}^{2} \\ {x}^{2} = 73.96 + 132.25 \\ x = \sqrt{206.21} \\ x = 14.185 \\ x = 14.19[/tex]
14.19
Mia opens a new savings account with $675 from her birthday last week.
* The bank pays 8% annual simple interest
* She makes no other deposits or withdrawals
What would be her total interest in her account, at the end of 4 years?
Answer:
$891
Step-by-step explanation:
This is Your Answer: $891, Steps below
The bakers at healthy bakery can make 320 bagels in 10 hours. How many bagels can they make in 15 hours? What was the rate per hour?
[tex]\qquad\qquad\huge\underline{{\sf Answer}}♨[/tex]
Let's use Unitary method ~
[tex]\qquad \sf \dashrightarrow \:10 \:hr = 320 \: bagels[/tex]
[tex]\qquad \sf \dashrightarrow \: 1\: hr = (320 \div 10) \: bagels[/tex]
[tex]\qquad \sf \dashrightarrow \:1 \: hr = 32 \: bagels[/tex]
So, the rate per hour is 32 bagels ~
[tex]\qquad \sf \dashrightarrow \:15 \: hr = (15 \times 32) \: bagels[/tex]
[tex]\qquad \sf \dashrightarrow \:15 \: hr = 480\: bagels[/tex]
So, they can prepare 480 bagels in 15 hours
Answer:
480 bagels
Step-by-step explanation:
320 bagels in 10 hours.
⇒ 320 bagels = 10 hours
Divide 10 both sides to find the rate per hour:
⇒ 320/10 bagels = 10/10 hours
⇒ 32 bagels = 1 hours
Multiply 15 both sides to find the number of bagels in 15 hours
⇒ 32 bagels = 1 hours
⇒ 32 x 15 bagels = 1 x 15 hours
⇒ 480 bagels = 15 hours
