Subtract 15/90 from 40/21
1st number: 1 19/21, 2nd number: 15/90
40/21 - 15/90 is 73/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 21 × 30 = 630,
40/21 = 40 × 30/21 × 30 = 1200/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
15/90 = 15 × 7/90 × 7 = 105/630 - Subtract the two like fractions:
1200/630 - 105/630 = 1200 - 105/630 = 1095/630 - After reducing the fraction, the answer is 73/42
- In mixed form: 131/42
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