Subtract 15/40 from 70/90
70/90 - 15/40 is 29/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
70/90 = 70 × 4/90 × 4 = 280/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
15/40 = 15 × 9/40 × 9 = 135/360 - Subtract the two like fractions:
280/360 - 135/360 = 280 - 135/360 = 145/360 - After reducing the fraction, the answer is 29/72
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