Subtract 21/90 from 42/35
1st number: 1 7/35, 2nd number: 21/90
42/35 - 21/90 is 29/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 35 × 18 = 630,
42/35 = 42 × 18/35 × 18 = 756/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
21/90 = 21 × 7/90 × 7 = 147/630 - Subtract the two like fractions:
756/630 - 147/630 = 756 - 147/630 = 609/630 - After reducing the fraction, the answer is 29/30
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