Add 21/36 and 42/63
21/36 + 42/63 is 5/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 63 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 63 × 4 = 252,
42/63 = 42 × 4/63 × 4 = 168/252 - Add the two like fractions:
147/252 + 168/252 = 147 + 168/252 = 315/252 - 315/252 simplified gives 5/4
- So, 21/36 + 42/63 = 5/4
In mixed form: 11/4
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