Subtract 24/15 from 90/70, Solve 1 20/70

Subtract 24/15 from 90/70

1^st number: 1 20/70, 2^nd number: 1 9/15

90/70 - 24/15 is -11/35.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 15 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 70 × 3 = 210,
90/70 = 90 × 3/70 × 3 = 270/210
Likewise, for the 2nd fraction, since 15 × 14 = 210,
24/15 = 24 × 14/15 × 14 = 336/210
Subtract the two like fractions:
270/210 - 336/210 = 270 - 336/210 = -66/210
After reducing the fraction, the answer is -11/35

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