Subtract 30/48 from 21/40
21/40 - 30/48 is -1/10.
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,
30/48 = 30 × 5/48 × 5 = 150/240 - Subtract the two like fractions:
126/240 - 150/240 = 126 - 150/240 = -24/240 - After reducing the fraction, the answer is -1/10
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