Add 40/70 and 30/42
40/70 + 30/42 is 9/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
40/70 = 40 × 3/70 × 3 = 120/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
30/42 = 30 × 5/42 × 5 = 150/210 - Add the two like fractions:
120/210 + 150/210 = 120 + 150/210 = 270/210 - 270/210 simplified gives 9/7
- So, 40/70 + 30/42 = 9/7
In mixed form: 12/7
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