Subtract 21/48 from 42/72
42/72 - 21/48 is 7/48.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 48 is 144
Next, find the equivalent fraction of both fractional numbers with denominator 144 - For the 1st fraction, since 72 × 2 = 144,
42/72 = 42 × 2/72 × 2 = 84/144 - Likewise, for the 2nd fraction, since 48 × 3 = 144,
21/48 = 21 × 3/48 × 3 = 63/144 - Subtract the two like fractions:
84/144 - 63/144 = 84 - 63/144 = 21/144 - After reducing the fraction, the answer is 7/48
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