Add 21/7 and 84/20
1st number: 3 0/7, 2nd number: 4 4/20
21/7 + 84/20 is 36/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 7 × 20 = 140,
21/7 = 21 × 20/7 × 20 = 420/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
84/20 = 84 × 7/20 × 7 = 588/140 - Add the two like fractions:
420/140 + 588/140 = 420 + 588/140 = 1008/140 - 1008/140 simplified gives 36/5
- So, 21/7 + 84/20 = 36/5
In mixed form: 71/5
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