Subtract 4/84 from 20/15, Solve 1 5/15

Subtract 4/84 from 20/15

1^st number: 1 5/15, 2^nd number: 4/84

20/15 - 4/84 is 9/7.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 84 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 15 × 28 = 420,
20/15 = 20 × 28/15 × 28 = 560/420
Likewise, for the 2nd fraction, since 84 × 5 = 420,
4/84 = 4 × 5/84 × 5 = 20/420
Subtract the two like fractions:
560/420 - 20/420 = 560 - 20/420 = 540/420
After reducing the fraction, the answer is 9/7
In mixed form: 12/7

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