Add 40/21 and 7/15, Solve 1 19/21 + 7/15 as a fraction

Add 40/21 and 7/15

1^st number: 1 19/21, 2^nd number: 7/15

40/21 + 7/15 is 83/35.

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,
40/21 = 40 × 5/21 × 5 = 200/105
Likewise, for the 2nd fraction, since 15 × 7 = 105,
7/15 = 7 × 7/15 × 7 = 49/105
Add the two like fractions:
200/105 + 49/105 = 200 + 49/105 = 249/105
249/105 simplified gives 83/35
So, 40/21 + 7/15 = 83/35
In mixed form: 213/35

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