Subtract 21/30 from 90/35, Solve 2 20/35

Subtract 21/30 from 90/35

1^st number: 2 20/35, 2^nd number: 21/30

90/35 - 21/30 is 131/70.

Find the least common denominator or LCM of the two denominators:
LCM of 35 and 30 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 35 × 6 = 210,
90/35 = 90 × 6/35 × 6 = 540/210
Likewise, for the 2nd fraction, since 30 × 7 = 210,
21/30 = 21 × 7/30 × 7 = 147/210
Subtract the two like fractions:
540/210 - 147/210 = 540 - 147/210 = 393/210
After reducing the fraction, the answer is 131/70
In mixed form: 161/70

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