Add 21/42 and 54/15
1st number: 21/42, 2nd number: 3 9/15
21/42 + 54/15 is 41/10.
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,
54/15 = 54 × 14/15 × 14 = 756/210 - Add the two like fractions:
105/210 + 756/210 = 105 + 756/210 = 861/210 - 861/210 simplified gives 41/10
- So, 21/42 + 54/15 = 41/10
In mixed form: 41/10
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