Add 21/20 and 9/15, Solve 1 1/20 + 9/15 as a fraction

Add 21/20 and 9/15

1^st number: 1 1/20, 2^nd number: 9/15

21/20 + 9/15 is 33/20.

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,
9/15 = 9 × 4/15 × 4 = 36/60
Add the two like fractions:
63/60 + 36/60 = 63 + 36/60 = 99/60
99/60 simplified gives 33/20
So, 21/20 + 9/15 = 33/20
In mixed form: 113/20

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