Answer: 9 laps in 1 day = 18 laps in 2 days
Explanation:
To complete the proportion, we can use the fact that the number of laps is directly proportional to the number of days:
9 laps in 1 day = 18 laps in x days
To solve for x, we can use the property of proportions that the product of the means equals the product of the extremes:
9 laps × x days = 1 day × 18 laps
Simplifying, we get:
9x = 18
Dividing both sides by 9, we get:
x = 2
Therefore, the missing number to complete the proportion is 2. The complete proportion is:
9 laps in 1 day = 18 laps in 2 days