Subtract 90/48 from 21/40
1st number: 21/40, 2nd number: 1 42/48
21/40 - 90/48 is -27/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 48 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 40 × 6 = 240,
21/40 = 21 × 6/40 × 6 = 126/240 - Likewise, for the 2nd fraction, since 48 × 5 = 240,
90/48 = 90 × 5/48 × 5 = 450/240 - Subtract the two like fractions:
126/240 - 450/240 = 126 - 450/240 = -324/240 - After reducing the fraction, the answer is -27/20
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