Add 15/21 and 90/42
1st number: 15/21, 2nd number: 2 6/42
15/21 + 90/42 is 20/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
15/21 = 15 × 2/21 × 2 = 30/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
90/42 = 90 × 1/42 × 1 = 90/42 - Add the two like fractions:
30/42 + 90/42 = 30 + 90/42 = 120/42 - 120/42 simplified gives 20/7
- So, 15/21 + 90/42 = 20/7
In mixed form: 26/7
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