Add 40/70 and 42/21
1st number: 40/70, 2nd number: 2 0/21
40/70 + 42/21 is 18/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 21 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 21 × 10 = 210,
42/21 = 42 × 10/21 × 10 = 420/210 - Add the two like fractions:
120/210 + 420/210 = 120 + 420/210 = 540/210 - 540/210 simplified gives 18/7
- So, 40/70 + 42/21 = 18/7
In mixed form: 24/7
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