Subtract 40/25 from 21/28
1st number: 21/28, 2nd number: 1 15/25
21/28 - 40/25 is -17/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 25 is 700
Next, find the equivalent fraction of both fractional numbers with denominator 700 - For the 1st fraction, since 28 × 25 = 700,
21/28 = 21 × 25/28 × 25 = 525/700 - Likewise, for the 2nd fraction, since 25 × 28 = 700,
40/25 = 40 × 28/25 × 28 = 1120/700 - Subtract the two like fractions:
525/700 - 1120/700 = 525 - 1120/700 = -595/700 - After reducing the fraction, the answer is -17/20
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