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

Add 10/21 and 40/15

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

10/21 + 40/15 is 22/7.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 21 × 5 = 105,
10/21 = 10 × 5/21 × 5 = 50/105
Likewise, for the 2nd fraction, since 15 × 7 = 105,
40/15 = 40 × 7/15 × 7 = 280/105
Add the two like fractions:
50/105 + 280/105 = 50 + 280/105 = 330/105
330/105 simplified gives 22/7
So, 10/21 + 40/15 = 22/7
In mixed form: 31/7

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