Subtract 21/20 from 42/24, Solve 1 18/24

Subtract 21/20 from 42/24

1^st number: 1 18/24, 2^nd number: 1 1/20

42/24 - 21/20 is 7/10.

Find the least common denominator or LCM of the two denominators:
LCM of 24 and 20 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 24 × 5 = 120,
42/24 = 42 × 5/24 × 5 = 210/120
Likewise, for the 2nd fraction, since 20 × 6 = 120,
21/20 = 21 × 6/20 × 6 = 126/120
Subtract the two like fractions:
210/120 - 126/120 = 210 - 126/120 = 84/120
After reducing the fraction, the answer is 7/10

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