Add 21/42 and 21/15
1st number: 21/42, 2nd number: 1 6/15
21/42 + 21/15 is 19/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 15 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210 - Likewise, for the 2nd fraction, since 15 × 14 = 210,
21/15 = 21 × 14/15 × 14 = 294/210 - Add the two like fractions:
105/210 + 294/210 = 105 + 294/210 = 399/210 - 399/210 simplified gives 19/10
- So, 21/42 + 21/15 = 19/10
In mixed form: 19/10
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