Subtract 21/45 from 42/35, Solve 1 7/35

Subtract 21/45 from 42/35

1^st number: 1 7/35, 2^nd number: 21/45

42/35 - 21/45 is 11/15.

Find the least common denominator or LCM of the two denominators:
LCM of 35 and 45 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 35 × 9 = 315,
42/35 = 42 × 9/35 × 9 = 378/315
Likewise, for the 2nd fraction, since 45 × 7 = 315,
21/45 = 21 × 7/45 × 7 = 147/315
Subtract the two like fractions:
378/315 - 147/315 = 378 - 147/315 = 231/315
After reducing the fraction, the answer is 11/15

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