Add 72/80 and 21/40
72/80 + 21/40 is 57/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 40 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 80 × 1 = 80,
72/80 = 72 × 1/80 × 1 = 72/80 - Likewise, for the 2nd fraction, since 40 × 2 = 80,
21/40 = 21 × 2/40 × 2 = 42/80 - Add the two like fractions:
72/80 + 42/80 = 72 + 42/80 = 114/80 - 114/80 simplified gives 57/40
- So, 72/80 + 21/40 = 57/40
In mixed form: 117/40
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