Subtract 7/64 from 21/18, Solve 1 3/18

Subtract 7/64 from 21/18

1^st number: 1 3/18, 2^nd number: 7/64

21/18 - 7/64 is 203/192.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 64 is 576

Next, find the equivalent fraction of both fractional numbers with denominator 576
For the 1st fraction, since 18 × 32 = 576,
21/18 = 21 × 32/18 × 32 = 672/576
Likewise, for the 2nd fraction, since 64 × 9 = 576,
7/64 = 7 × 9/64 × 9 = 63/576
Subtract the two like fractions:
672/576 - 63/576 = 672 - 63/576 = 609/576
After reducing the fraction, the answer is 203/192
In mixed form: 111/192

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