Add 3/15 and 21/42
3/15 + 21/42 is 7/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 15 × 14 = 210,
3/15 = 3 × 14/15 × 14 = 42/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210 - Add the two like fractions:
42/210 + 105/210 = 42 + 105/210 = 147/210 - 147/210 simplified gives 7/10
- So, 3/15 + 21/42 = 7/10
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