Subtract 70/45 from 21/30
1st number: 21/30, 2nd number: 1 25/45
21/30 - 70/45 is -77/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
21/30 = 21 × 3/30 × 3 = 63/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
70/45 = 70 × 2/45 × 2 = 140/90 - Subtract the two like fractions:
63/90 - 140/90 = 63 - 140/90 = -77/90
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