Subtract 21/15 from 42/80
1st number: 42/80, 2nd number: 1 6/15
42/80 - 21/15 is -7/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 15 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 80 × 3 = 240,
42/80 = 42 × 3/80 × 3 = 126/240 - Likewise, for the 2nd fraction, since 15 × 16 = 240,
21/15 = 21 × 16/15 × 16 = 336/240 - Subtract the two like fractions:
126/240 - 336/240 = 126 - 336/240 = -210/240 - After reducing the fraction, the answer is -7/8
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