Subtract 21/7 from 90/36
1st number: 2 18/36, 2nd number: 3 0/7
90/36 - 21/7 is -1/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 7 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 36 × 7 = 252,
90/36 = 90 × 7/36 × 7 = 630/252 - Likewise, for the 2nd fraction, since 7 × 36 = 252,
21/7 = 21 × 36/7 × 36 = 756/252 - Subtract the two like fractions:
630/252 - 756/252 = 630 - 756/252 = -126/252 - After reducing the fraction, the answer is -1/2
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