Add 25/15 and 4/21, Solve 1 10/15 + 4/21 as a fraction

Add 25/15 and 4/21

1^st number: 1 10/15, 2^nd number: 4/21

25/15 + 4/21 is 13/7.

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

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 15 × 7 = 105,
25/15 = 25 × 7/15 × 7 = 175/105
Likewise, for the 2nd fraction, since 21 × 5 = 105,
4/21 = 4 × 5/21 × 5 = 20/105
Add the two like fractions:
175/105 + 20/105 = 175 + 20/105 = 195/105
195/105 simplified gives 13/7
So, 25/15 + 4/21 = 13/7
In mixed form: 16/7

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