Subtract 1/40 from 42/45
42/45 - 1/40 is 109/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 45 × 8 = 360,
42/45 = 42 × 8/45 × 8 = 336/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
1/40 = 1 × 9/40 × 9 = 9/360 - Subtract the two like fractions:
336/360 - 9/360 = 336 - 9/360 = 327/360 - After reducing the fraction, the answer is 109/120
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