Subtract 20/40 from 15/7, Solve 2 1/7

Subtract 20/40 from 15/7

1^st number: 2 1/7, 2^nd number: 20/40

15/7 - 20/40 is 23/14.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 40 is 280

Next, find the equivalent fraction of both fractional numbers with denominator 280
For the 1st fraction, since 7 × 40 = 280,
15/7 = 15 × 40/7 × 40 = 600/280
Likewise, for the 2nd fraction, since 40 × 7 = 280,
20/40 = 20 × 7/40 × 7 = 140/280
Subtract the two like fractions:
600/280 - 140/280 = 600 - 140/280 = 460/280
After reducing the fraction, the answer is 23/14
In mixed form: 19/14

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