Subtract 15/21 from 98/20, Solve 4 18/20

Subtract 15/21 from 98/20

1^st number: 4 18/20, 2^nd number: 15/21

98/20 - 15/21 is 293/70.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 20 × 21 = 420,
98/20 = 98 × 21/20 × 21 = 2058/420
Likewise, for the 2nd fraction, since 21 × 20 = 420,
15/21 = 15 × 20/21 × 20 = 300/420
Subtract the two like fractions:
2058/420 - 300/420 = 2058 - 300/420 = 1758/420
After reducing the fraction, the answer is 293/70
In mixed form: 413/70

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