Subtract 42/48 from 21/45
21/45 - 42/48 is -49/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 48 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 45 × 16 = 720,
21/45 = 21 × 16/45 × 16 = 336/720 - Likewise, for the 2nd fraction, since 48 × 15 = 720,
42/48 = 42 × 15/48 × 15 = 630/720 - Subtract the two like fractions:
336/720 - 630/720 = 336 - 630/720 = -294/720 - After reducing the fraction, the answer is -49/120
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