Add 24/15 and 21/42, Solve 1 9/15 + 21/42 as a fraction

Add 24/15 and 21/42

1^st number: 1 9/15, 2^nd number: 21/42

24/15 + 21/42 is 21/10.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 15 × 14 = 210,
24/15 = 24 × 14/15 × 14 = 336/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210
Add the two like fractions:
336/210 + 105/210 = 336 + 105/210 = 441/210
441/210 simplified gives 21/10
So, 24/15 + 21/42 = 21/10
In mixed form: 21/10

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