Subtract 21/70 from 40/60, Solve 40/60

Subtract 21/70 from 40/60

40/60 - 21/70 is 11/30.

Find the least common denominator or LCM of the two denominators:
LCM of 60 and 70 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 60 × 7 = 420,
40/60 = 40 × 7/60 × 7 = 280/420
Likewise, for the 2nd fraction, since 70 × 6 = 420,
21/70 = 21 × 6/70 × 6 = 126/420
Subtract the two like fractions:
280/420 - 126/420 = 280 - 126/420 = 154/420
After reducing the fraction, the answer is 11/30

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