Subtract 21/9 from 42/40
1st number: 1 2/40, 2nd number: 2 3/9
42/40 - 21/9 is -77/60.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 9 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
42/40 = 42 × 9/40 × 9 = 378/360 - Likewise, for the 2nd fraction, since 9 × 40 = 360,
21/9 = 21 × 40/9 × 40 = 840/360 - Subtract the two like fractions:
378/360 - 840/360 = 378 - 840/360 = -462/360 - After reducing the fraction, the answer is -77/60
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