Add 90/70 and 30/18
1st number: 1 20/70, 2nd number: 1 12/18
90/70 + 30/18 is 62/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 18 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 18 × 35 = 630,
30/18 = 30 × 35/18 × 35 = 1050/630 - Add the two like fractions:
810/630 + 1050/630 = 810 + 1050/630 = 1860/630 - 1860/630 simplified gives 62/21
- So, 90/70 + 30/18 = 62/21
In mixed form: 220/21
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