Add 15/10 and 40/21
1st number: 1 5/10, 2nd number: 1 19/21
15/10 + 40/21 is 143/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 10 × 21 = 210,
15/10 = 15 × 21/10 × 21 = 315/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
40/21 = 40 × 10/21 × 10 = 400/210 - Add the two like fractions:
315/210 + 400/210 = 315 + 400/210 = 715/210 - 715/210 simplified gives 143/42
- So, 15/10 + 40/21 = 143/42
In mixed form: 317/42
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