I am having problems with the following question, can u help?
The Sun is approximately 1,400 million kilometers from the planet Saturn, and light from the Sun travels to Saturn at a rate of 300,000 kilometers per second. Approximately, how many MINUTES does it take for light to travel from the Sun to Saturn?
a. 80
b. 130
c. 160
d. 280
e. 360
Ans: A
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- kginena
- Students
- Posts: 7
- Joined: Mon May 14, 2012 2:31 am
- glenda.lezeau
- Prospective Students
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- Joined: Mon May 07, 2012 6:34 pm
Re: The Sun is approximately 1,400 million kilometers
Hi,
I am not too sure but is the answer A? If so, what I did was use the equation rate=distance/time. Plug in the rate and time. You will get 300,000=1,400,000,000/time. (300,000)(time)=1,400,000,000 and then divide 300,000 on both sides to get time alone. Time will equal 46666.6666 seconds. It is in seconds since your distance was in kilometers per second. In order to change into minutes, divide 46666.6666 seconds by 60 and you will get 77.7777 minutes. The question asked for an approximation so 77.7777 minutes will round to 80 minutes.
I hope this helps/is right.
~Glenda
I am not too sure but is the answer A? If so, what I did was use the equation rate=distance/time. Plug in the rate and time. You will get 300,000=1,400,000,000/time. (300,000)(time)=1,400,000,000 and then divide 300,000 on both sides to get time alone. Time will equal 46666.6666 seconds. It is in seconds since your distance was in kilometers per second. In order to change into minutes, divide 46666.6666 seconds by 60 and you will get 77.7777 minutes. The question asked for an approximation so 77.7777 minutes will round to 80 minutes.
I hope this helps/is right.
~Glenda
- kginena
- Students
- Posts: 7
- Joined: Mon May 14, 2012 2:31 am
Re: The Sun is approximately 1,400 million kilometers
great job Glenda. Yes, A) is the correct answer.
For some reason I got to the 46666 figure and then messed up with the next division. I guess I couldn't get my head around how the answer would start with a 8 until I read your remark that it is an approximation.
For some reason I got to the 46666 figure and then messed up with the next division. I guess I couldn't get my head around how the answer would start with a 8 until I read your remark that it is an approximation.
- esledge
- Posts: 23
- Joined: Wed Apr 06, 2011 7:09 am
Re: The Sun is approximately 1,400 million kilometers
Looks like you two worked this out--great job! Alternatively, you could hold off on doing any calculator work until you have simplified as much as possible on paper.
Convert the Rate to be in terms of minutes. If light travels 300,000 kilometers per second, it travels 300,000 * 60 = 18,000,000 kilometers per minute. Pause here to count your zeros! 5 zeros from 300,000 and 1 zero from 60, for a total of 6 zeros. Since a million has 6 zeros, we could also say that the Rate = 18 million kilometers per minute.
Time = Distance/Rate = 1,400 million kilometers/18 million kilometers per minute.
Cancel the million kilometers from both top and bottom:
Time = Distance/Rate = (1,400 /18) minutes
Then, all you have to plug into the calculator is 1400/18.
Convert the Rate to be in terms of minutes. If light travels 300,000 kilometers per second, it travels 300,000 * 60 = 18,000,000 kilometers per minute. Pause here to count your zeros! 5 zeros from 300,000 and 1 zero from 60, for a total of 6 zeros. Since a million has 6 zeros, we could also say that the Rate = 18 million kilometers per minute.
Time = Distance/Rate = 1,400 million kilometers/18 million kilometers per minute.
Cancel the million kilometers from both top and bottom:
Time = Distance/Rate = (1,400 /18) minutes
Then, all you have to plug into the calculator is 1400/18.
4 posts Page 1 of 1