Add 80/70 and 15/90
1st number: 1 10/70, 2nd number: 15/90
80/70 + 15/90 is 55/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
80/70 = 80 × 9/70 × 9 = 720/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
15/90 = 15 × 7/90 × 7 = 105/630 - Add the two like fractions:
720/630 + 105/630 = 720 + 105/630 = 825/630 - 825/630 simplified gives 55/42
- So, 80/70 + 15/90 = 55/42
In mixed form: 113/42
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