Add 15/70 and 40/21
1st number: 15/70, 2nd number: 1 19/21
15/70 + 40/21 is 89/42.
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,
15/70 = 15 × 3/70 × 3 = 45/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
40/21 = 40 × 10/21 × 10 = 400/210 - Add the two like fractions:
45/210 + 400/210 = 45 + 400/210 = 445/210 - 445/210 simplified gives 89/42
- So, 15/70 + 40/21 = 89/42
In mixed form: 25/42
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