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

Add 25/21 and 4/15

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

25/21 + 4/15 is 51/35.

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,
25/21 = 25 × 5/21 × 5 = 125/105
Likewise, for the 2nd fraction, since 15 × 7 = 105,
4/15 = 4 × 7/15 × 7 = 28/105
Add the two like fractions:
125/105 + 28/105 = 125 + 28/105 = 153/105
153/105 simplified gives 51/35
So, 25/21 + 4/15 = 51/35
In mixed form: 116/35

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