Subtract 90/21 from 4/15
1st number: 4/15, 2nd number: 4 6/21
4/15 - 90/21 is -422/105.
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,
4/15 = 4 × 7/15 × 7 = 28/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
90/21 = 90 × 5/21 × 5 = 450/105 - Subtract the two like fractions:
28/105 - 450/105 = 28 - 450/105 = -422/105
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