Add 9/40 and 72/30, Solve 9/40 + 2 12/30 as a fraction

Add 9/40 and 72/30

1^st number: 9/40, 2^nd number: 2 12/30

9/40 + 72/30 is 21/8.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 30 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 40 × 3 = 120,
9/40 = 9 × 3/40 × 3 = 27/120
Likewise, for the 2nd fraction, since 30 × 4 = 120,
72/30 = 72 × 4/30 × 4 = 288/120
Add the two like fractions:
27/120 + 288/120 = 27 + 288/120 = 315/120
315/120 simplified gives 21/8
So, 9/40 + 72/30 = 21/8
In mixed form: 25/8

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