Add 36/40 and 81/60, Solve 36/40 + 1 21/60 as a fraction

Add 36/40 and 81/60

1^st number: 36/40, 2^nd number: 1 21/60

36/40 + 81/60 is 9/4.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 60 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 40 × 3 = 120,
36/40 = 36 × 3/40 × 3 = 108/120
Likewise, for the 2nd fraction, since 60 × 2 = 120,
81/60 = 81 × 2/60 × 2 = 162/120
Add the two like fractions:
108/120 + 162/120 = 108 + 162/120 = 270/120
270/120 simplified gives 9/4
So, 36/40 + 81/60 = 9/4
In mixed form: 21/4

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