Add 42/21 and 20/28
1st number: 2 0/21, 2nd number: 20/28
42/21 + 20/28 is 19/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
42/21 = 42 × 4/21 × 4 = 168/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
20/28 = 20 × 3/28 × 3 = 60/84 - Add the two like fractions:
168/84 + 60/84 = 168 + 60/84 = 228/84 - 228/84 simplified gives 19/7
- So, 42/21 + 20/28 = 19/7
In mixed form: 25/7
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