Add 15/18 and 21/70
15/18 + 21/70 is 17/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 18 × 35 = 630,
15/18 = 15 × 35/18 × 35 = 525/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
21/70 = 21 × 9/70 × 9 = 189/630 - Add the two like fractions:
525/630 + 189/630 = 525 + 189/630 = 714/630 - 714/630 simplified gives 17/15
- So, 15/18 + 21/70 = 17/15
In mixed form: 12/15
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