Subtract 81/70 from 90/30
1st number: 3 0/30, 2nd number: 1 11/70
90/30 - 81/70 is 129/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
90/30 = 90 × 7/30 × 7 = 630/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
81/70 = 81 × 3/70 × 3 = 243/210 - Subtract the two like fractions:
630/210 - 243/210 = 630 - 243/210 = 387/210 - After reducing the fraction, the answer is 129/70
- In mixed form: 159/70
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