Subtract 18/7 from 35/20, Solve 1 15/20

Subtract 18/7 from 35/20

1^st number: 1 15/20, 2^nd number: 2 4/7

35/20 - 18/7 is -23/28.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 7 is 140

Next, find the equivalent fraction of both fractional numbers with denominator 140
For the 1st fraction, since 20 × 7 = 140,
35/20 = 35 × 7/20 × 7 = 245/140
Likewise, for the 2nd fraction, since 7 × 20 = 140,
18/7 = 18 × 20/7 × 20 = 360/140
Subtract the two like fractions:
245/140 - 360/140 = 245 - 360/140 = -115/140
After reducing the fraction, the answer is -23/28

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