Subtract 15/30 from 80/21
1st number: 3 17/21, 2nd number: 15/30
80/21 - 15/30 is 139/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
80/21 = 80 × 10/21 × 10 = 800/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
15/30 = 15 × 7/30 × 7 = 105/210 - Subtract the two like fractions:
800/210 - 105/210 = 800 - 105/210 = 695/210 - After reducing the fraction, the answer is 139/42
- In mixed form: 313/42
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