Add 20/90 and 15/21
20/90 + 15/21 is 59/63.
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,
15/21 = 15 × 30/21 × 30 = 450/630 - Add the two like fractions:
140/630 + 450/630 = 140 + 450/630 = 590/630 - 590/630 simplified gives 59/63
- So, 20/90 + 15/21 = 59/63
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