Question

you are traveling in europe and you notice the speed limit is 90 km/h. how many miles per hour is that? (round your answer nearest tenths) reminder : 1 mile = 1.61 kilometers mph question 4 1 pts convert 100 m/s into miles per hour. (round your answer to four significants figures) reminder: 1 mile = 1610 meter 1 heure = 3600 seconds

Explanation:

Step1: Convert kilometers to miles

Given \(1\) mile \( = 1.61\) kilometers. To convert \(90\) km/h to mph, we use the formula \(v_{mph}=\frac{v_{km/h}}{1.61}\).
So, \(v_{mph}=\frac{90}{1.61}\)

Step2: Calculate the value

\(\frac{90}{1.61}\approx55.9\) (rounded to the nearest tenths)

Step3: Convert \(100\) m/s to mph

First, convert meters to miles: \(1\) mile \( = 1610\) meters, so \(1\) meter \(=\frac{1}{1610}\) miles.
Second, convert seconds to hours: \(1\) hour \( = 3600\) seconds, so \(1\) second \(=\frac{1}{3600}\) hours.
The conversion formula for \(v\) (in m/s) to mph is \(v_{mph}=v\times\frac{3600}{1610}\)
For \(v = 100\) m/s, \(v_{mph}=100\times\frac{3600}{1610}=\frac{360000}{1610}\approx223.6\) (rounded to four significant figures)

Answer:

For the first question: \(55.9\) mph
For the second question: \(223.6\) mph