Add 21/8 and 90/18
1st number: 2 5/8, 2nd number: 5 0/18
21/8 + 90/18 is 61/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 18 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 18 × 4 = 72,
90/18 = 90 × 4/18 × 4 = 360/72 - Add the two like fractions:
189/72 + 360/72 = 189 + 360/72 = 549/72 - 549/72 simplified gives 61/8
- So, 21/8 + 90/18 = 61/8
In mixed form: 75/8
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