Subtract 90/7 from 42/45, Solve 42/45

Subtract 90/7 from 42/45

1^st number: 42/45, 2^nd number: 12 6/7

42/45 - 90/7 is -1252/105.

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

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 45 × 7 = 315,
42/45 = 42 × 7/45 × 7 = 294/315
Likewise, for the 2nd fraction, since 7 × 45 = 315,
90/7 = 90 × 45/7 × 45 = 4050/315
Subtract the two like fractions:
294/315 - 4050/315 = 294 - 4050/315 = -3756/315
After reducing the fraction, the answer is -1252/105

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