Subtract 21/42 from 60/90, Solve 60/90

Subtract 21/42 from 60/90

60/90 - 21/42 is 1/6.

Find the least common denominator or LCM of the two denominators:
LCM of 90 and 42 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 90 × 7 = 630,
60/90 = 60 × 7/90 × 7 = 420/630
Likewise, for the 2nd fraction, since 42 × 15 = 630,
21/42 = 21 × 15/42 × 15 = 315/630
Subtract the two like fractions:
420/630 - 315/630 = 420 - 315/630 = 105/630
After reducing the fraction, the answer is 1/6

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