Add 20/70 and 42/45
20/70 + 42/45 is 128/105.
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,
42/45 = 42 × 14/45 × 14 = 588/630 - Add the two like fractions:
180/630 + 588/630 = 180 + 588/630 = 768/630 - 768/630 simplified gives 128/105
- So, 20/70 + 42/45 = 128/105
In mixed form: 123/105
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