Subtract 7/40 from 21/15, Solve 1 6/15

Subtract 7/40 from 21/15

1^st number: 1 6/15, 2^nd number: 7/40

21/15 - 7/40 is 49/40.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 40 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 15 × 8 = 120,
21/15 = 21 × 8/15 × 8 = 168/120
Likewise, for the 2nd fraction, since 40 × 3 = 120,
7/40 = 7 × 3/40 × 3 = 21/120
Subtract the two like fractions:
168/120 - 21/120 = 168 - 21/120 = 147/120
After reducing the fraction, the answer is 49/40
In mixed form: 19/40

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