Add 21/42 and 9/15
21/42 + 9/15 is 11/10.
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,
9/15 = 9 × 14/15 × 14 = 126/210 - Add the two like fractions:
105/210 + 126/210 = 105 + 126/210 = 231/210 - 231/210 simplified gives 11/10
- So, 21/42 + 9/15 = 11/10
In mixed form: 11/10
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