Add 70/21 and 10/90
1st number: 3 7/21, 2nd number: 10/90
70/21 + 10/90 is 31/9.
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,
70/21 = 70 × 30/21 × 30 = 2100/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
10/90 = 10 × 7/90 × 7 = 70/630 - Add the two like fractions:
2100/630 + 70/630 = 2100 + 70/630 = 2170/630 - 2170/630 simplified gives 31/9
- So, 70/21 + 10/90 = 31/9
In mixed form: 34/9
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