Add 42/45 and 21/15
1st number: 42/45, 2nd number: 1 6/15
42/45 + 21/15 is 7/3.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 15 is 45
Next, find the equivalent fraction of both fractional numbers with denominator 45 - For the 1st fraction, since 45 × 1 = 45,
42/45 = 42 × 1/45 × 1 = 42/45 - Likewise, for the 2nd fraction, since 15 × 3 = 45,
21/15 = 21 × 3/15 × 3 = 63/45 - Add the two like fractions:
42/45 + 63/45 = 42 + 63/45 = 105/45 - 105/45 simplified gives 7/3
- So, 42/45 + 21/15 = 7/3
In mixed form: 21/3
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