Subtract 21/10 from 42/72
1st number: 42/72, 2nd number: 2 1/10
42/72 - 21/10 is -91/60.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 10 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
42/72 = 42 × 5/72 × 5 = 210/360 - Likewise, for the 2nd fraction, since 10 × 36 = 360,
21/10 = 21 × 36/10 × 36 = 756/360 - Subtract the two like fractions:
210/360 - 756/360 = 210 - 756/360 = -546/360 - After reducing the fraction, the answer is -91/60
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