Add 90/72 and 21/56
1st number: 1 18/72, 2nd number: 21/56
90/72 + 21/56 is 13/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 56 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
90/72 = 90 × 7/72 × 7 = 630/504 - Likewise, for the 2nd fraction, since 56 × 9 = 504,
21/56 = 21 × 9/56 × 9 = 189/504 - Add the two like fractions:
630/504 + 189/504 = 630 + 189/504 = 819/504 - 819/504 simplified gives 13/8
- So, 90/72 + 21/56 = 13/8
In mixed form: 15/8
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