1/8 - 7/20 as a fraction

Learn how to find what is 1/8 minus 7/20 in fraction form just in a few minutes. We have covered the easiest method to write 1/8 - 7/20 as a fraction and decimal.

Summary: 1/8 minus 7/20 = -9/40
Since both fractions have unequal denominators, 1/8 minus 7/20 is an unlike fractions subtraction. For subtracting unlike fractions, you have to first find the equivalent fractions for fraction 1/8 and fraction 7/20 in order to have the same denominators for both fractions. Therefore, you have to find the LCM of denominators 8 and 20. 40 is the LCM of 8 and 20. Multiplying the LCM 40 with the numerators and denominators of both fractions (1/8 x 40/40) - (7/20 x 40/40), and simplify further in order to have the common denominator. So the equivalent fraction for 1/8 is 5/40 and for 7/20 is 14/40. By simplifying this fraction subtraction 5/40 - 14/40, it becomes -9/40.

CALCULATION: 1/8 - 7/20 as a fraction
1/8 - 7/20 = (?)
1/8 - 7/20 = [(1 x 20) - (7 x 8)]/(8 x 20)
= (20 - 56)/160
= -36/160
= (4 x -9)/(4 x 40)
= -9/40
1/8 - 7/20 = -9/40
1/8 minus 7/20 as a fraction is -9/40.

where
1/8 is a proper fraction as a minuend,
7/20 is a proper fraction as a subtrahend,
-9/40 is the difference between 1/8 and 7/20.

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1/8 minus 7/20 as a decimal
1/8 - 7/20 = -9/40
-9/40 = -0.225
(1/8) - (7/20) as a decimal is -0.225

where
-0.225 is the difference between 1/8 and 7/20.

The below workout with step by step calculation shows how to find what is the difference between two fractions by subtracting a fraction 7/20 from 1/8. For different, unequal or unlike denominators, use any one of the following methods to find the equivalent fraction for 1/8 minus 7/20.
1. LCM method
2. Cross multiplication method.

(1/8) - (7/20) using LCM Method:
What is 1/8 minus 7/20 as a fraction?

step 1 Observe the input parameters and what to be found:
Input:
Fraction A: 1/8
Fraction B: 7/20

What to be found?
(1/8) - (7/20) = ?
Find what's the difference between 1/8 and 7/20.

step 2 Compare the denominators of fractions 1/8 and 7/20 to identify whether it is a like or unlike fraction subtraction. Since the denominators of given fractions 1/8 and 7/20 are not equal, it is said to be unlike fractions subtraction.

step 3For unlike fractions subtraction, find the LCM (least common multiple) of both denominators of fractions 1/8 and 7/20:
The LCM of 8 and 20 is 40.

step 4 Write the fractions 1/8 and 7/20 in the subtraction expression form and multiply LCM with all the numerators and denominators of both fractions.
= 1/8 - 7/20
= [(1 x 40)/(8 x 40)] - [(7 x 40)/(20 x 40)]

step 5 Simplify the expression to have common denominator:
= 5/40 - 14/40

step 6 Take the common values out and rewrite the above expression like the below:
= 1/40 x (5/1 - 14/1)
= 1/40 x (5 - 14)

step 7Simplify the above expression further:
= 1/40 x -9
= -9/40
1/8 - 7/20 = -9/40

Hence,
1/8 minus 7/20 as a fraction is -9/40.

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1/8 - 7/20 using Cross Multiplication Method:
step 1 Observe the input parameters and what to be found:
Input:
Fraction A: 1/8
Fraction B: 7/20

What to be found?
(1/8)-(7/20) = ?
Find what's the difference between 1/8 and 7/20.

step 2 Find the product of numerator of Fraction A and denominator of Fraction B (1 x 20), find the product of numerator of Fraction B and denominator of Fraction A (7 x 8), and find the product of both denominators of Fraction A and Fraction B (8 x 20) and rewrite the equation as like the below:
= (1 x 20) - (7 x 8)/(8 x 20)

step 3 Simplify and rewrite the fraction:
= (20 - 56)/160
= -36/160
= -9/40
1/8 - 7/20 = -9/40

Hence,
1/8 minus 7/20 in fraction is -9/40