Question 3 (1.4 points) Recently I bought a set of tire chains that I could use

Question

Question 3 (1.4 points) Recently I bought a set of tire chains that I could use on my car during the winter. These chains wrap around the outside of the tire. Last week I bought a new set of tires. The new tires are 2 inches taller than the old ones. The tire chains are now too short. How long of a piece of chain do I need to add to the existing chains so that they will wrap around the outside of my new tires? Your Answer: Answer Save Question 4 (1.4 points) I was driving on Interstate 90 and noticed in my rear view mirror a car that was rapidly approaching. I look at my speedometer and saw that I was going 76 miles per hour (I had my cruise control on). When the fast car passed me, I looked at my watch and began to count the number of seconds that had passed. I saw a bridge in the distance. When I reached 11 seconds, the fast car drove past the bridge. I continued to count and at 12 seconds, I drove past the same bridge How fast (miles per hour) was the other car going? Your Answer: Answer

Explanation / Answer

Ans 3: Suppose the diameter of original tyre is "a" inches then the diameter of new tire is "a+2".

To wrap the original tire the length of chain should be equal to the circumference of tire thais is (pi*a) = (22/7)*a

Circumference of new tire= (22/7)*(a+2)

The length of the chain to be added is the difference of circumference of both tires :

= (22/7)*(a+2-a) = (22/7)*2 = (44/7) inches

Ans 4: According to question distance travelled by the fast car in 12 seconds is equal to the distance travelled by me in 11 seconds & my speed is given as 76 miles per hour.

Let the speed of fast car be "a" miles per hour.

1 hour = 3600 seconds so 12 seconds = (12/3600) hours and 11 seconds = 11/3600 hours

So, a*11/3600 = 76*12/3600 11a = 912 a = 912/11 = 82.9

So the speed of the fast car is 82.9 miles per hour

Related Questions

Navigate

• Browse (All)
• Browse Q
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.