Add 42/40 and 81/30, Solve 1 2/40 + 2 21/30 as a fraction

Add 42/40 and 81/30

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

42/40 + 81/30 is 15/4.

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,
42/40 = 42 × 3/40 × 3 = 126/120
Likewise, for the 2nd fraction, since 30 × 4 = 120,
81/30 = 81 × 4/30 × 4 = 324/120
Add the two like fractions:
126/120 + 324/120 = 126 + 324/120 = 450/120
450/120 simplified gives 15/4
So, 42/40 + 81/30 = 15/4
In mixed form: 33/4

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