Subtract 80/21 from 70/15
1st number: 4 10/15, 2nd number: 3 17/21
70/15 - 80/21 is 6/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
70/15 = 70 × 7/15 × 7 = 490/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
80/21 = 80 × 5/21 × 5 = 400/105 - Subtract the two like fractions:
490/105 - 400/105 = 490 - 400/105 = 90/105 - After reducing the fraction, the answer is 6/7
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