Add 15/2 and 42/21
1st number: 7 1/2, 2nd number: 2 0/21
15/2 + 42/21 is 19/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 2 × 21 = 42,
15/2 = 15 × 21/2 × 21 = 315/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
42/21 = 42 × 2/21 × 2 = 84/42 - Add the two like fractions:
315/42 + 84/42 = 315 + 84/42 = 399/42 - 399/42 simplified gives 19/2
- So, 15/2 + 42/21 = 19/2
In mixed form: 91/2
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