Add 10/40 and 42/15, Solve 10/40 + 2 12/15 as a fraction

Add 10/40 and 42/15

1^st number: 10/40, 2^nd number: 2 12/15

10/40 + 42/15 is 61/20.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 15 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 40 × 3 = 120,
10/40 = 10 × 3/40 × 3 = 30/120
Likewise, for the 2nd fraction, since 15 × 8 = 120,
42/15 = 42 × 8/15 × 8 = 336/120
Add the two like fractions:
30/120 + 336/120 = 30 + 336/120 = 366/120
366/120 simplified gives 61/20
So, 10/40 + 42/15 = 61/20
In mixed form: 31/20

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