Add 18/21 and 40/70
18/21 + 40/70 is 10/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
18/21 = 18 × 10/21 × 10 = 180/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
40/70 = 40 × 3/70 × 3 = 120/210 - Add the two like fractions:
180/210 + 120/210 = 180 + 120/210 = 300/210 - 300/210 simplified gives 10/7
- So, 18/21 + 40/70 = 10/7
In mixed form: 13/7
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