Add 42/72 and 9/20
42/72 + 9/20 is 31/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 20 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
42/72 = 42 × 5/72 × 5 = 210/360 - Likewise, for the 2nd fraction, since 20 × 18 = 360,
9/20 = 9 × 18/20 × 18 = 162/360 - Add the two like fractions:
210/360 + 162/360 = 210 + 162/360 = 372/360 - 372/360 simplified gives 31/30
- So, 42/72 + 9/20 = 31/30
In mixed form: 11/30
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