Add 21/10 and 42/80
1st number: 2 1/10, 2nd number: 42/80
21/10 + 42/80 is 21/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 80 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 10 × 8 = 80,
21/10 = 21 × 8/10 × 8 = 168/80 - Likewise, for the 2nd fraction, since 80 × 1 = 80,
42/80 = 42 × 1/80 × 1 = 42/80 - Add the two like fractions:
168/80 + 42/80 = 168 + 42/80 = 210/80 - 210/80 simplified gives 21/8
- So, 21/10 + 42/80 = 21/8
In mixed form: 25/8
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