Subtract 28/70 from 21/8
1st number: 2 5/8, 2nd number: 28/70
21/8 - 28/70 is 89/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 70 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 8 × 35 = 280,
21/8 = 21 × 35/8 × 35 = 735/280 - Likewise, for the 2nd fraction, since 70 × 4 = 280,
28/70 = 28 × 4/70 × 4 = 112/280 - Subtract the two like fractions:
735/280 - 112/280 = 735 - 112/280 = 623/280 - After reducing the fraction, the answer is 89/40
- In mixed form: 29/40
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