Add 20/70 and 42/90
20/70 + 42/90 is 79/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
20/70 = 20 × 9/70 × 9 = 180/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
42/90 = 42 × 7/90 × 7 = 294/630 - Add the two like fractions:
180/630 + 294/630 = 180 + 294/630 = 474/630 - 474/630 simplified gives 79/105
- So, 20/70 + 42/90 = 79/105
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