Subtract 42/90 from 28/21
1st number: 1 7/21, 2nd number: 42/90
28/21 - 42/90 is 13/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 21 × 30 = 630,
28/21 = 28 × 30/21 × 30 = 840/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
42/90 = 42 × 7/90 × 7 = 294/630 - Subtract the two like fractions:
840/630 - 294/630 = 840 - 294/630 = 546/630 - After reducing the fraction, the answer is 13/15
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