Add 21/15 and 90/7
1st number: 1 6/15, 2nd number: 12 6/7
21/15 + 90/7 is 499/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 7 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
21/15 = 21 × 7/15 × 7 = 147/105 - Likewise, for the 2nd fraction, since 7 × 15 = 105,
90/7 = 90 × 15/7 × 15 = 1350/105 - Add the two like fractions:
147/105 + 1350/105 = 147 + 1350/105 = 1497/105 - 1497/105 simplified gives 499/35
- So, 21/15 + 90/7 = 499/35
In mixed form: 149/35
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