Subtract 42/48 from 30/40
30/40 - 42/48 is -1/8.
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,
30/40 = 30 × 6/40 × 6 = 180/240 - Likewise, for the 2nd fraction, since 48 × 5 = 240,
42/48 = 42 × 5/48 × 5 = 210/240 - Subtract the two like fractions:
180/240 - 210/240 = 180 - 210/240 = -30/240 - After reducing the fraction, the answer is -1/8
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