Add 21/90 and 25/8
1st number: 21/90, 2nd number: 3 1/8
21/90 + 25/8 is 403/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 8 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
21/90 = 21 × 4/90 × 4 = 84/360 - Likewise, for the 2nd fraction, since 8 × 45 = 360,
25/8 = 25 × 45/8 × 45 = 1125/360 - Add the two like fractions:
84/360 + 1125/360 = 84 + 1125/360 = 1209/360 - 1209/360 simplified gives 403/120
- So, 21/90 + 25/8 = 403/120
In mixed form: 343/120
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