Add 90/20 and 42/72
1st number: 4 10/20, 2nd number: 42/72
90/20 + 42/72 is 61/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 20 × 18 = 360,
90/20 = 90 × 18/20 × 18 = 1620/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
42/72 = 42 × 5/72 × 5 = 210/360 - Add the two like fractions:
1620/360 + 210/360 = 1620 + 210/360 = 1830/360 - 1830/360 simplified gives 61/12
- So, 90/20 + 42/72 = 61/12
In mixed form: 51/12
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