The rate of a bus that rolls down a hill is directly proportional to the length of time it rolls.At the end of 15 seconds, its rate is 35 mph. How long will it take the bus to have a rate of 48 mph?
x/48 = 15/35
Hsha
To solve this problem, we can set up a proportionality equation using the given information.
Let's denote the rate of the bus as r (mph) and the time it rolls as t (seconds).
According to the problem, we know that when t = 15 seconds, r = 35 mph.
We can set up the proportionality equation as follows:
r/t = k
where k is the constant of proportionality.
Substituting the given values, we have:
35 mph / 15 seconds = k
Simplifying this equation, we find:
k = 35/15 mph/seconds
Now, we can use the value of k to find the time it takes for the rate to be 48 mph.
48 mph / (35/15 mph/seconds) = t
Simplifying the equation further, we have:
48 mph * (15 seconds/35 mph) = t
Therefore, it will take the bus approximately 20.57 seconds to have a rate of 48 mph.
To solve this problem, we can use the concept of direct proportionality. We know that the rate of the bus is directly proportional to the length of time it rolls. This means that if we double the time, the rate will also double, and if we triple the time, the rate will triple, and so on.
Let's set up a proportion to solve the problem:
(rate at 15 seconds) / (time at 15 seconds) = (rate at unknown time) / (unknown time)
Using the information given, we can substitute the values into the proportion:
35 mph / 15 s = 48 mph / x
To solve for x, the unknown time, we cross-multiply:
35 mph * x = 48 mph * 15 s
35x = 720
Now, we can isolate x by dividing both sides of the equation by 35:
x = 720 / 35
Using a calculator, we can find that x is approximately equal to 20.57 seconds.
Therefore, it will take the bus approximately 20.57 seconds to reach a rate of 48 mph.