Add 70/90 and 63/21
1st number: 70/90, 2nd number: 3 0/21
70/90 + 63/21 is 34/9.
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,
70/90 = 70 × 7/90 × 7 = 490/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
63/21 = 63 × 30/21 × 30 = 1890/630 - Add the two like fractions:
490/630 + 1890/630 = 490 + 1890/630 = 2380/630 - 2380/630 simplified gives 34/9
- So, 70/90 + 63/21 = 34/9
In mixed form: 37/9
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