Subtract 42/16 from 21/15
1st number: 1 6/15, 2nd number: 2 10/16
21/15 - 42/16 is -49/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 16 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 15 × 16 = 240,
21/15 = 21 × 16/15 × 16 = 336/240 - Likewise, for the 2nd fraction, since 16 × 15 = 240,
42/16 = 42 × 15/16 × 15 = 630/240 - Subtract the two like fractions:
336/240 - 630/240 = 336 - 630/240 = -294/240 - After reducing the fraction, the answer is -49/40
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