Subtract 7/40 from 84/63, Solve 1 21/63

Subtract 7/40 from 84/63

1^st number: 1 21/63, 2^nd number: 7/40

84/63 - 7/40 is 139/120.

Find the least common denominator or LCM of the two denominators:
LCM of 63 and 40 is 2520

Next, find the equivalent fraction of both fractional numbers with denominator 2520
For the 1st fraction, since 63 × 40 = 2520,
84/63 = 84 × 40/63 × 40 = 3360/2520
Likewise, for the 2nd fraction, since 40 × 63 = 2520,
7/40 = 7 × 63/40 × 63 = 441/2520
Subtract the two like fractions:
3360/2520 - 441/2520 = 3360 - 441/2520 = 2919/2520
After reducing the fraction, the answer is 139/120
In mixed form: 119/120

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