Add 21/36 and 15/42
21/36 + 15/42 is 79/84.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 42 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 36 × 7 = 252,
21/36 = 21 × 7/36 × 7 = 147/252 - Likewise, for the 2nd fraction, since 42 × 6 = 252,
15/42 = 15 × 6/42 × 6 = 90/252 - Add the two like fractions:
147/252 + 90/252 = 147 + 90/252 = 237/252 - 237/252 simplified gives 79/84
- So, 21/36 + 15/42 = 79/84
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