Add 42/10 and 80/21
1st number: 4 2/10, 2nd number: 3 17/21
42/10 + 80/21 is 841/105.
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,
80/21 = 80 × 10/21 × 10 = 800/210 - Add the two like fractions:
882/210 + 800/210 = 882 + 800/210 = 1682/210 - 1682/210 simplified gives 841/105
- So, 42/10 + 80/21 = 841/105
In mixed form: 81/105
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