Add 42/72 and 75/90
42/72 + 75/90 is 17/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 90 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 90 × 4 = 360,
75/90 = 75 × 4/90 × 4 = 300/360 - Add the two like fractions:
210/360 + 300/360 = 210 + 300/360 = 510/360 - 510/360 simplified gives 17/12
- So, 42/72 + 75/90 = 17/12
In mixed form: 15/12
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