Subtract 42/80 from 7/15, Solve 7/15

Subtract 42/80 from 7/15

7/15 - 42/80 is -7/120.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 80 is 240

Next, find the equivalent fraction of both fractional numbers with denominator 240
For the 1st fraction, since 15 × 16 = 240,
7/15 = 7 × 16/15 × 16 = 112/240
Likewise, for the 2nd fraction, since 80 × 3 = 240,
42/80 = 42 × 3/80 × 3 = 126/240
Subtract the two like fractions:
112/240 - 126/240 = 112 - 126/240 = -14/240
After reducing the fraction, the answer is -7/120

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