Add 20/70 and 15/45
20/70 + 15/45 is 13/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 45 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
20/70 = 20 × 9/70 × 9 = 180/630 - Likewise, for the 2nd fraction, since 45 × 14 = 630,
15/45 = 15 × 14/45 × 14 = 210/630 - Add the two like fractions:
180/630 + 210/630 = 180 + 210/630 = 390/630 - 390/630 simplified gives 13/21
- So, 20/70 + 15/45 = 13/21
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