Add 15/21 and 90/25, Solve 15/21 + 3 15/25 as a fraction

Add 15/21 and 90/25

1^st number: 15/21, 2^nd number: 3 15/25

15/21 + 90/25 is 151/35.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 25 is 525

Next, find the equivalent fraction of both fractional numbers with denominator 525
For the 1st fraction, since 21 × 25 = 525,
15/21 = 15 × 25/21 × 25 = 375/525
Likewise, for the 2nd fraction, since 25 × 21 = 525,
90/25 = 90 × 21/25 × 21 = 1890/525
Add the two like fractions:
375/525 + 1890/525 = 375 + 1890/525 = 2265/525
2265/525 simplified gives 151/35
So, 15/21 + 90/25 = 151/35
In mixed form: 411/35

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