Add 21/42 and 35/90, Solve 21/42 + 35/90 as a fraction

Add 21/42 and 35/90

21/42 + 35/90 is 8/9.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 90 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 42 × 15 = 630,
21/42 = 21 × 15/42 × 15 = 315/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
35/90 = 35 × 7/90 × 7 = 245/630
Add the two like fractions:
315/630 + 245/630 = 315 + 245/630 = 560/630
560/630 simplified gives 8/9
So, 21/42 + 35/90 = 8/9

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