Add 15/70 and 80/90
15/70 + 80/90 is 139/126.
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,
15/70 = 15 × 9/70 × 9 = 135/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
80/90 = 80 × 7/90 × 7 = 560/630 - Add the two like fractions:
135/630 + 560/630 = 135 + 560/630 = 695/630 - 695/630 simplified gives 139/126
- So, 15/70 + 80/90 = 139/126
In mixed form: 113/126
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