Subtract 7/8 from 10/21
1021 - 78 is -67168.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
1021 = 10 × 821 × 8 = 80168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
78 = 7 × 218 × 21 = 147168 - Subtract the two like fractions:
80168 - 147168 = 80 - 147168 = -67168
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