Add 42/70 and 80/21
1st number: 42/70, 2nd number: 3 17/21
42/70 + 80/21 is 463/105.
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,
42/70 = 42 × 3/70 × 3 = 126/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
80/21 = 80 × 10/21 × 10 = 800/210 - Add the two like fractions:
126/210 + 800/210 = 126 + 800/210 = 926/210 - 926/210 simplified gives 463/105
- So, 42/70 + 80/21 = 463/105
In mixed form: 443/105
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