Add 15/40 and 81/72, Solve 15/40 + 1 9/72 as a fraction

Add 15/40 and 81/72

1^st number: 15/40, 2^nd number: 1 9/72

15/40 + 81/72 is 3/2.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 72 is 360

Next, find the equivalent fraction of both fractional numbers with denominator 360
For the 1st fraction, since 40 × 9 = 360,
15/40 = 15 × 9/40 × 9 = 135/360
Likewise, for the 2nd fraction, since 72 × 5 = 360,
81/72 = 81 × 5/72 × 5 = 405/360
Add the two like fractions:
135/360 + 405/360 = 135 + 405/360 = 540/360
540/360 simplified gives 3/2
So, 15/40 + 81/72 = 3/2
In mixed form: 11/2

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