Add 40/21 and 15/35, Solve 1 19/21 + 15/35 as a fraction

Add 40/21 and 15/35

1^st number: 1 19/21, 2^nd number: 15/35

40/21 + 15/35 is 7/3.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 35 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 35 × 3 = 105,
15/35 = 15 × 3/35 × 3 = 45/105
Add the two like fractions:
200/105 + 45/105 = 200 + 45/105 = 245/105
245/105 simplified gives 7/3
So, 40/21 + 15/35 = 7/3
In mixed form: 21/3

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