Add 18/20 and 42/80
18/20 + 42/80 is 57/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 80 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 20 × 4 = 80,
18/20 = 18 × 4/20 × 4 = 72/80 - Likewise, for the 2nd fraction, since 80 × 1 = 80,
42/80 = 42 × 1/80 × 1 = 42/80 - Add the two like fractions:
72/80 + 42/80 = 72 + 42/80 = 114/80 - 114/80 simplified gives 57/40
- So, 18/20 + 42/80 = 57/40
In mixed form: 117/40
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