Add 40/15 and 21/84, Solve 2 10/15 + 21/84 as a fraction

Add 40/15 and 21/84

1^st number: 2 10/15, 2^nd number: 21/84

40/15 + 21/84 is 35/12.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 84 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 15 × 28 = 420,
40/15 = 40 × 28/15 × 28 = 1120/420
Likewise, for the 2nd fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420
Add the two like fractions:
1120/420 + 105/420 = 1120 + 105/420 = 1225/420
1225/420 simplified gives 35/12
So, 40/15 + 21/84 = 35/12
In mixed form: 211/12

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