Add 18/21 and 40/25, Solve 18/21 + 1 15/25 as a fraction

Add 18/21 and 40/25

1^st number: 18/21, 2^nd number: 1 15/25

18/21 + 40/25 is 86/35.

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,
18/21 = 18 × 25/21 × 25 = 450/525
Likewise, for the 2nd fraction, since 25 × 21 = 525,
40/25 = 40 × 21/25 × 21 = 840/525
Add the two like fractions:
450/525 + 840/525 = 450 + 840/525 = 1290/525
1290/525 simplified gives 86/35
So, 18/21 + 40/25 = 86/35
In mixed form: 216/35

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