Add 12/35 and 42/90
12/35 + 42/90 is 17/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 35 × 18 = 630,
12/35 = 12 × 18/35 × 18 = 216/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
42/90 = 42 × 7/90 × 7 = 294/630 - Add the two like fractions:
216/630 + 294/630 = 216 + 294/630 = 510/630 - 510/630 simplified gives 17/21
- So, 12/35 + 42/90 = 17/21
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