Add 10/21 and 70/90
10/21 + 70/90 is 79/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 21 × 30 = 630,
10/21 = 10 × 30/21 × 30 = 300/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
70/90 = 70 × 7/90 × 7 = 490/630 - Add the two like fractions:
300/630 + 490/630 = 300 + 490/630 = 790/630 - 790/630 simplified gives 79/63
- So, 10/21 + 70/90 = 79/63
In mixed form: 116/63
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