Add 21/63 and 40/42
21/63 + 40/42 is 9/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 42 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 63 × 2 = 126,
21/63 = 21 × 2/63 × 2 = 42/126 - Likewise, for the 2nd fraction, since 42 × 3 = 126,
40/42 = 40 × 3/42 × 3 = 120/126 - Add the two like fractions:
42/126 + 120/126 = 42 + 120/126 = 162/126 - 162/126 simplified gives 9/7
- So, 21/63 + 40/42 = 9/7
In mixed form: 12/7
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