Add 45/70 and 15/90
45/70 + 15/90 is 17/21.
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,
45/70 = 45 × 9/70 × 9 = 405/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
15/90 = 15 × 7/90 × 7 = 105/630 - Add the two like fractions:
405/630 + 105/630 = 405 + 105/630 = 510/630 - 510/630 simplified gives 17/21
- So, 45/70 + 15/90 = 17/21
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