Add 90/20 and 18/72
1st number: 4 10/20, 2nd number: 18/72
90/20 + 18/72 is 19/4.
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,
18/72 = 18 × 5/72 × 5 = 90/360 - Add the two like fractions:
1620/360 + 90/360 = 1620 + 90/360 = 1710/360 - 1710/360 simplified gives 19/4
- So, 90/20 + 18/72 = 19/4
In mixed form: 43/4
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