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The car is moving in a constant rate. By what percent will the distance decrease if the speed is decreased by 25% and the time is decreased by 50%?

User Atru
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1 Answer

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Final answer:

To calculate the percent decrease in distance when the speed is decreased by 25% and the time is decreased by 50%, we can use the distance formula and the percent decrease formula. The distance will decrease by 62.5%.

Step-by-step explanation:

To calculate the percent decrease in distance, we need to first understand the relationship between speed, time, and distance. The formula to calculate distance is:

Distance = Speed x Time

Let's assume the initial speed is represented by S and the initial time is represented by T. We are given that the speed is decreased by 25%, so the new speed is 0.75S (75% of the initial speed). The time is decreased by 50%, so the new time is 0.5T (50% of the initial time).

Using the distance formula, we can calculate the initial distance (D1) and the new distance (D2):

D1 = S x T

D2 = 0.75S x 0.5T = 0.375ST

To calculate the percent decrease in distance, we can use the following formula:

Percent decrease = ((D1 - D2) / D1) x 100

Substituting the values, we get:

Percent decrease = ((S x T - 0.375ST) / (S x T)) x 100

Simplifying the equation further, we get:

Percent decrease = (1 - 0.375) x 100 = 62.5%

User Arahant
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