Add 42/15 and 21/24, Solve 2 12/15 + 21/24 as a fraction

Add 42/15 and 21/24

1^st number: 2 12/15, 2^nd number: 21/24

42/15 + 21/24 is 147/40.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 24 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 15 × 8 = 120,
42/15 = 42 × 8/15 × 8 = 336/120
Likewise, for the 2nd fraction, since 24 × 5 = 120,
21/24 = 21 × 5/24 × 5 = 105/120
Add the two like fractions:
336/120 + 105/120 = 336 + 105/120 = 441/120
441/120 simplified gives 147/40
So, 42/15 + 21/24 = 147/40
In mixed form: 327/40

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