Add 21/15 and 90/72
1st number: 1 6/15, 2nd number: 1 18/72
21/15 + 90/72 is 53/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 15 × 24 = 360,
21/15 = 21 × 24/15 × 24 = 504/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
90/72 = 90 × 5/72 × 5 = 450/360 - Add the two like fractions:
504/360 + 450/360 = 504 + 450/360 = 954/360 - 954/360 simplified gives 53/20
- So, 21/15 + 90/72 = 53/20
In mixed form: 213/20
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