Add 20/90 and 7/21
20/90 + 7/21 is 5/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
20/90 = 20 × 7/90 × 7 = 140/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
7/21 = 7 × 30/21 × 30 = 210/630 - Add the two like fractions:
140/630 + 210/630 = 140 + 210/630 = 350/630 - 350/630 simplified gives 5/9
- So, 20/90 + 7/21 = 5/9
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