Add 20/70 and 15/90
20/70 + 15/90 is 19/42.
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,
15/90 = 15 × 7/90 × 7 = 105/630 - Add the two like fractions:
180/630 + 105/630 = 180 + 105/630 = 285/630 - 285/630 simplified gives 19/42
- So, 20/70 + 15/90 = 19/42
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