Add 15/70 and 5/21
15/70 + 5/21 is 19/42.
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,
5/21 = 5 × 10/21 × 10 = 50/210 - Add the two like fractions:
45/210 + 50/210 = 45 + 50/210 = 95/210 - 95/210 simplified gives 19/42
- So, 15/70 + 5/21 = 19/42
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