IDNLearn.com: Where your questions meet expert advice and community support. Ask anything and receive thorough, reliable answers from our community of experienced professionals.

K
A speed of 30 miles per hour (mph) is equivalent to 48 kilometers per hour (km/h). Jane passes a sign stating that the
speed limit is 50 km/h. What is the speed limit in miles per hour?
The speed limit is
mph. (Round to the nearest hundredth as needed.)
DE


Sagot :

Question:

A speed of 30 miles per hour (mph) is equivalent to 48 kilometers per hour (km/h). Jane passes a sign stating that the speed limit is 50 km/h. What is the speed limit in miles per hour?

Answer:

The speed limit is 31.25 mph.

Step-by-step explanation:

1. Understand the given information:

  - 30 mph = 48 km/h

  - The speed limit is 50 km/h

  - We need to convert 50 km/h to mph

2. Set up a proportion to convert km/h to mph:

  30 mph / 48 km/h = x mph / 50 km/h

3. Cross multiply:

  30 * 50 = 48x

4. Solve for x:

  1500 = 48x

  x = 1500 / 48

5. Calculate the result:

  x = 31.25

Additional information:

This problem involves unit conversion and the use of proportions. The key is recognizing that the ratio between mph and km/h remains constant. Therefore, we can use the given equivalence (30 mph = 48 km/h) to set up a proportion and solve for the unknown speed in mph.

In real-world applications, it's important to note that speed limit signs are typically rounded to the nearest 5 or 10 units for practical reasons. So while the exact conversion is 31.25 mph, a actual speed limit sign in mph corresponding to 50 km/h would likely read 30 mph or 35 mph, depending on local regulations and rounding practices.

Step-by-step explanation:

well, 50 km/h is very close to 48 km/h.

so, the converted speed must also be very close to 30 mph (a little bit higher but very close).

in any case, there is the same conversion factor between 48 km/h and 30 mph on one hand and between 50 km/h and the converted x mph on the other hand.

so, the ratios must be equal :

48/30 = 50/x

48x/30 = 50

48x = 50×30 = 1500

x = 1500/48 = 375/12 = 125/4 = 31.25 mph

so, the speed limit is 31.25 mph.