Add 42/20 and 63/21
1st number: 2 2/20, 2nd number: 3 0/21
42/20 + 63/21 is 51/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
42/20 = 42 × 21/20 × 21 = 882/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
63/21 = 63 × 20/21 × 20 = 1260/420 - Add the two like fractions:
882/420 + 1260/420 = 882 + 1260/420 = 2142/420 - 2142/420 simplified gives 51/10
- So, 42/20 + 63/21 = 51/10
In mixed form: 51/10
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