Add 42/40 and 63/12, Solve 1 2/40 + 5 3/12 as a fraction

Add 42/40 and 63/12

1^st number: 1 2/40, 2^nd number: 5 3/12

42/40 + 63/12 is 63/10.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 12 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 12 × 10 = 120,
63/12 = 63 × 10/12 × 10 = 630/120
Add the two like fractions:
126/120 + 630/120 = 126 + 630/120 = 756/120
756/120 simplified gives 63/10
So, 42/40 + 63/12 = 63/10
In mixed form: 63/10

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