Add 21/20 and 18/15
1st number: 1 1/20, 2nd number: 1 3/15
21/20 + 18/15 is 9/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 15 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 20 × 3 = 60,
21/20 = 21 × 3/20 × 3 = 63/60 - Likewise, for the 2nd fraction, since 15 × 4 = 60,
18/15 = 18 × 4/15 × 4 = 72/60 - Add the two like fractions:
63/60 + 72/60 = 63 + 72/60 = 135/60 - 135/60 simplified gives 9/4
- So, 21/20 + 18/15 = 9/4
In mixed form: 21/4
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