Subtract 80/70 from 40/21
1st number: 1 19/21, 2nd number: 1 10/70
40/21 - 80/70 is 16/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
40/21 = 40 × 10/21 × 10 = 400/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
80/70 = 80 × 3/70 × 3 = 240/210 - Subtract the two like fractions:
400/210 - 240/210 = 400 - 240/210 = 160/210 - After reducing the fraction, the answer is 16/21
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