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Example Questions
Example Question #1557 : Act Math
Simplify the expression:
First you want to find the least common denominator (in this case it's 18):
Example Question #1 : How To Add Fractions
What is the result of adding of to ?
Let us first get our value for the percentage of the first fraction. 20% of 2/7 is found by multiplying 2/7 by 2/10 (or, simplified, 1/5): (2/7) * (1/5) = (2/35)
Our addition is therefore (2/35) + (1/4). There are no common factors, so the least common denominator will be 35 * 4 or 140. Multiply the numerator and denominator of 2/35 by 4/4 and the numerator of 1/4 by 35/35.
This yields:
(8/140) + (35/140) = 43/140, which cannot be reduced.
Example Question #12 : Operations And Fractions
Which of the following is equal to ?
We have two options here. We can manipulate the answers to work backwards and find a common denominator. This involves simply subtracting or adding two fractions. We can also try to rewrite the numerator by adding and subtracting the value . This serves the purpose of creating a sum in the numerator than can be split into and . This gives us one of the factors in the denominator in each numerator. When we separate or decompose the fraction, we can divide out by the common factor to re-express this as the difference of two rational expressions.
Example Question #1 : How To Find The Reciprocal Of A Fraction
What is the reciprocal of the fraction 3/727?
3/727
–727/3
727/3
–3/727
242
727/3
The reciprocal of a fraction is just switching the numerator (top number) and the denominator (bottom number). The negative reciprocal takes the negative of that number.
3/727
Reciprocal 727/3
Example Question #1 : How To Find The Reciprocal Of A Fraction
What is the opposite reciprocal of 25/127?
–5
25/127
127/25
–127/25
–25/127
–127/25
The reciprocal of a fraction is just switching the numerator (top number) and the denominator (bottom number). The opposite reciprocal takes the negative of that number.
Example Question #2 : How To Find The Reciprocal Of A Fraction
Find the negative reciprocal of the following:
The reciprocal of a fraction is just switching the numerator (top number) and the denominator (bottom number). The negative reciprocal takes the negative of that number.
Reciprocal
Negative Reciprocal
Example Question #1 : How To Find The Reciprocal Of A Fraction
What is the slope of any line perpendicular to 4y = 2x + 7 ?
First, we must solve the equation for y to determine the slope: y = (2/4)x + 7/4
By looking at the coefficient in front of x, we know that the slope of this line has a value of 1/2. To find the slope of any line perpendicular to this one, we take the negative reciprocal of it:
slope = m , perpendicular slope = –1/m
slope = 1/2 , perpendicular slope = –2
Example Question #1 : How To Find The Reciprocal Of A Fraction
Find the reciprocal of the following fraction
The reciprocal is defined such that a faction times its recprocal is 1. For you this just means turn the fraction upside down, ie the numerator is the denominator and vice versa.
Example Question #1 : How To Find The Reciprocal Of A Fraction
What is the reciprocal of ?
This fraction doesn't have a reciprocal.
The reciprocal of a fraction is simply exchanging the denominator and numerator of a fraction.
You can double check that it works by making sure the product of a fraction and its reciprocal is 1.
Example Question #1 : How To Find The Lowest / Least Common Denominator
What is the difference between the LCM and GCF for the following set of numbers: 3, 12, and 30?
48
57
75
None of the answers are correct
60
57
LCM = least common multiple = 2 x 2 x 3 x 5 = 60
GCF = greatest common factor = 3
Prime factor each number
3 = 3 x 1
12 = 3 x 4 = 3 x 2 x 2
30 = 5 x 6 = 5 x 2 x 3
LCM – GCF = 60 – 3 = 57