Add 10/90 and 8/21
10/90 + 8/21 is 31/63.
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,
10/90 = 10 × 7/90 × 7 = 70/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
8/21 = 8 × 30/21 × 30 = 240/630 - Add the two like fractions:
70/630 + 240/630 = 70 + 240/630 = 310/630 - 310/630 simplified gives 31/63
- So, 10/90 + 8/21 = 31/63
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