Subtract 21/8 from 70/18
1st number: 3 16/18, 2nd number: 2 5/8
70/18 - 21/8 is 91/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 8 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 18 × 4 = 72,
70/18 = 70 × 4/18 × 4 = 280/72 - Likewise, for the 2nd fraction, since 8 × 9 = 72,
21/8 = 21 × 9/8 × 9 = 189/72 - Subtract the two like fractions:
280/72 - 189/72 = 280 - 189/72 = 91/72 - In mixed form: 119/72
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