Add 15/90 and 20/70
15/90 + 20/70 is 19/42.
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,
15/90 = 15 × 7/90 × 7 = 105/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
20/70 = 20 × 9/70 × 9 = 180/630 - Add the two like fractions:
105/630 + 180/630 = 105 + 180/630 = 285/630 - 285/630 simplified gives 19/42
- So, 15/90 + 20/70 = 19/42
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