Add 20/42 and 30/70
20/42 + 30/70 is 19/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
20/42 = 20 × 5/42 × 5 = 100/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
30/70 = 30 × 3/70 × 3 = 90/210 - Add the two like fractions:
100/210 + 90/210 = 100 + 90/210 = 190/210 - 190/210 simplified gives 19/21
- So, 20/42 + 30/70 = 19/21
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