Subtract 4/72 from 21/45
21/45 - 4/72 is 37/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 45 × 8 = 360,
21/45 = 21 × 8/45 × 8 = 168/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
4/72 = 4 × 5/72 × 5 = 20/360 - Subtract the two like fractions:
168/360 - 20/360 = 168 - 20/360 = 148/360 - After reducing the fraction, the answer is 37/90
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