Subtract 28/72 from 21/35
21/35 - 28/72 is 19/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 72 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 35 × 72 = 2520,
21/35 = 21 × 72/35 × 72 = 1512/2520 - Likewise, for the 2nd fraction, since 72 × 35 = 2520,
28/72 = 28 × 35/72 × 35 = 980/2520 - Subtract the two like fractions:
1512/2520 - 980/2520 = 1512 - 980/2520 = 532/2520 - After reducing the fraction, the answer is 19/90
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