Add 15/8 and 21/90
1st number: 1 7/8, 2nd number: 21/90
15/8 + 21/90 is 253/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 90 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 8 × 45 = 360,
15/8 = 15 × 45/8 × 45 = 675/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
21/90 = 21 × 4/90 × 4 = 84/360 - Add the two like fractions:
675/360 + 84/360 = 675 + 84/360 = 759/360 - 759/360 simplified gives 253/120
- So, 15/8 + 21/90 = 253/120
In mixed form: 213/120
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