Add 21/7 and 9/20
1st number: 3 0/7, 2nd number: 9/20
21/7 + 9/20 is 69/20.
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,
9/20 = 9 × 7/20 × 7 = 63/140 - Add the two like fractions:
420/140 + 63/140 = 420 + 63/140 = 483/140 - 483/140 simplified gives 69/20
- So, 21/7 + 9/20 = 69/20
In mixed form: 39/20
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