Question

please help




Use any strategy to solve the problem.
The Science Club Treasurer finds that the bill for 18 sweatshirts ordered by the Science Club has two digits blurred by water damage. The bill reads _68.9_ The treasurer is sure that the first and last digits are the same, and that the price of each sweatshirt was between $10 and $15. Assumaing each of the sweatshirts cost the same amount, elect the total price.
a.
$168.91
c.
$368.93
b.
$268.92
d.
$468.94

Answer 1

If the price of a sweatshirt is between 10 and 15 dollars, then what are the bounds for the cost of 18 sweatshirts?

Answer 2

180

Answer 3

However, he wasn't sure how much they cost, just that the price per shirt was between 10 and 15 dollars. If each shirt cost 10 dollars, then 18 shirts cost 180 dollars indeed. But what if he was wrong and they actually cost 15 dollars per piece?

Answer 4

did you delete the reply?

Answer 5

Yes, English was a bit ugly :) Its there again.

Answer 6

yea

Answer 7

idk

Answer 8

Well you had the first half correct :) Ignore the rest of the information for now. All we have to know is that 18 shirts were bought, and that the shirts were between 10 and 15 dollars per piece. Of course, all shirts cost the same.

Answer 9

If the shirts were 10 dollars, the total cost would be 180 dollars, as you said. That was the cheapest option, so answer a) is impossible.
The maximum price of a shirt is 15 dollars, in which case 18 shirts cost how much?

Answer 10

270?

Answer 11

Correct :) Now can you determine which answers are incorrect as well as a)?

Answer 12

You just calculated the two extreme options: Either all shirts were the cheapest option (180 in total), or they were the most expensive (270 in total).
So, 18 shirts cost between 180 and 270 dollars if each shirt costs 10-15 dollars.

Answer 13

you think it is D?

Answer 14

If it is D, then how much would one shirt cost? 468.94/18 = ?

Answer 15

nevermind, im dumb lol, im confused

Answer 16

We won't settle for that :) Lets check again, the important information:

" the bill for 18 sweatshirts"

"the price of each sweatshirt was between $10 and $15. Assuming each of the sweatshirts cost the same amount,"

Answer 17

This means that, as you calculated, the minimum and maximum price of 18 sweatshirts is?

Answer 18

When you have the minimum and maximum prices, you can see that three answers are impossible :)

Answer 19

ok we know it is not D and i think it is not C?

Answer 20

Why can it not be C? Not that your choice is wrong but we should check the reasoning :)

Answer 21

because i thought that it is too much money

Answer 22

Correct. It is $ 368.93, but if the shirts were $ 15 per piece (which was the most expensive guess by the treasurer) the price would be?

Answer 23

D?

Answer 24

We know now that the price of the 18 shirts was between 180 and 270 dollars, because each shirt costs 10-15 dollars. Then, only one answer is possible.

Answer 25

oh B?

Answer 26

Correct :)

Answer 27

thanks so much ;)

Answer 28

No problem, hope it is clear :)