Add 90/70 and 12/9
1st number: 1 20/70, 2nd number: 1 3/9
90/70 + 12/9 is 55/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 9 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
90/70 = 90 × 9/70 × 9 = 810/630 - Likewise, for the 2nd fraction, since 9 × 70 = 630,
12/9 = 12 × 70/9 × 70 = 840/630 - Add the two like fractions:
810/630 + 840/630 = 810 + 840/630 = 1650/630 - 1650/630 simplified gives 55/21
- So, 90/70 + 12/9 = 55/21
In mixed form: 213/21
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