Add 18/15 and 21/25, Solve 1 3/15 + 21/25 as a fraction

Add 18/15 and 21/25

1^st number: 1 3/15, 2^nd number: 21/25

18/15 + 21/25 is 51/25.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 25 is 75

Next, find the equivalent fraction of both fractional numbers with denominator 75
For the 1st fraction, since 15 × 5 = 75,
18/15 = 18 × 5/15 × 5 = 90/75
Likewise, for the 2nd fraction, since 25 × 3 = 75,
21/25 = 21 × 3/25 × 3 = 63/75
Add the two like fractions:
90/75 + 63/75 = 90 + 63/75 = 153/75
153/75 simplified gives 51/25
So, 18/15 + 21/25 = 51/25
In mixed form: 21/25

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