Subtract 21/45 from 70/75
70/75 - 21/45 is 7/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 75 and 45 is 225
Next, find the equivalent fraction of both fractional numbers with denominator 225 - For the 1st fraction, since 75 × 3 = 225,
70/75 = 70 × 3/75 × 3 = 210/225 - Likewise, for the 2nd fraction, since 45 × 5 = 225,
21/45 = 21 × 5/45 × 5 = 105/225 - Subtract the two like fractions:
210/225 - 105/225 = 210 - 105/225 = 105/225 - After reducing the fraction, the answer is 7/15
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