Add 42/90 and 24/70
42/90 + 24/70 is 17/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
42/90 = 42 × 7/90 × 7 = 294/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
24/70 = 24 × 9/70 × 9 = 216/630 - Add the two like fractions:
294/630 + 216/630 = 294 + 216/630 = 510/630 - 510/630 simplified gives 17/21
- So, 42/90 + 24/70 = 17/21
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