Subtract 42/70 from 21/7
1st number: 3 0/7, 2nd number: 42/70
21/7 - 42/70 is 12/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 70 is 70
Next, find the equivalent fraction of both fractional numbers with denominator 70 - For the 1st fraction, since 7 × 10 = 70,
21/7 = 21 × 10/7 × 10 = 210/70 - Likewise, for the 2nd fraction, since 70 × 1 = 70,
42/70 = 42 × 1/70 × 1 = 42/70 - Subtract the two like fractions:
210/70 - 42/70 = 210 - 42/70 = 168/70 - After reducing the fraction, the answer is 12/5
- In mixed form: 22/5
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