Add 42/10 and 84/21
1st number: 4 2/10, 2nd number: 4 0/21
42/10 + 84/21 is 41/5.
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,
42/10 = 42 × 21/10 × 21 = 882/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
84/21 = 84 × 10/21 × 10 = 840/210 - Add the two like fractions:
882/210 + 840/210 = 882 + 840/210 = 1722/210 - 1722/210 simplified gives 41/5
- So, 42/10 + 84/21 = 41/5
In mixed form: 81/5
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