Subtract 21/72 from 42/7, Solve 6 0/7

Subtract 21/72 from 42/7

1^st number: 6 0/7, 2^nd number: 21/72

42/7 - 21/72 is 137/24.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 72 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 7 × 72 = 504,
42/7 = 42 × 72/7 × 72 = 3024/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
21/72 = 21 × 7/72 × 7 = 147/504
Subtract the two like fractions:
3024/504 - 147/504 = 3024 - 147/504 = 2877/504
After reducing the fraction, the answer is 137/24
In mixed form: 517/24

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