Subtract 21/45 from 8/7, Solve 1 1/7

Subtract 21/45 from 8/7

1^st number: 1 1/7, 2^nd number: 21/45

8/7 - 21/45 is 71/105.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 45 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 7 × 45 = 315,
8/7 = 8 × 45/7 × 45 = 360/315
Likewise, for the 2nd fraction, since 45 × 7 = 315,
21/45 = 21 × 7/45 × 7 = 147/315
Subtract the two like fractions:
360/315 - 147/315 = 360 - 147/315 = 213/315
After reducing the fraction, the answer is 71/105

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