Add 21/40 and 75/30, Solve 21/40 + 2 15/30 as a fraction

Add 21/40 and 75/30

1^st number: 21/40, 2^nd number: 2 15/30

21/40 + 75/30 is 121/40.

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,
21/40 = 21 × 3/40 × 3 = 63/120
Likewise, for the 2nd fraction, since 30 × 4 = 120,
75/30 = 75 × 4/30 × 4 = 300/120
Add the two like fractions:
63/120 + 300/120 = 63 + 300/120 = 363/120
363/120 simplified gives 121/40
So, 21/40 + 75/30 = 121/40
In mixed form: 31/40

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