Subtract 21/28 from 90/70
1st number: 1 20/70, 2nd number: 21/28
90/70 - 21/28 is 15/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 28 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 70 × 2 = 140,
90/70 = 90 × 2/70 × 2 = 180/140 - Likewise, for the 2nd fraction, since 28 × 5 = 140,
21/28 = 21 × 5/28 × 5 = 105/140 - Subtract the two like fractions:
180/140 - 105/140 = 180 - 105/140 = 75/140 - After reducing the fraction, the answer is 15/28
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