Subtract 40/21 from 90/15
1st number: 6 0/15, 2nd number: 1 19/21
90/15 - 40/21 is 86/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
90/15 = 90 × 7/15 × 7 = 630/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
40/21 = 40 × 5/21 × 5 = 200/105 - Subtract the two like fractions:
630/105 - 200/105 = 630 - 200/105 = 430/105 - After reducing the fraction, the answer is 86/21
- In mixed form: 42/21
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