Add 21/8 and 90/72
1st number: 2 5/8, 2nd number: 1 18/72
21/8 + 90/72 is 31/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 72 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 8 × 9 = 72,
21/8 = 21 × 9/8 × 9 = 189/72 - Likewise, for the 2nd fraction, since 72 × 1 = 72,
90/72 = 90 × 1/72 × 1 = 90/72 - Add the two like fractions:
189/72 + 90/72 = 189 + 90/72 = 279/72 - 279/72 simplified gives 31/8
- So, 21/8 + 90/72 = 31/8
In mixed form: 37/8
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