Question

Please Help!!!! Fan and Medal!!!!!!

Theo finds a large container of batteries in a basement. He randomly selects and tests 14 of the batteries and finds that 4 of them do not work. There are 76 batteries in the container. Which is the best prediction for the number of batteries that will not work?

A.
18

B.
22

C.
29

D.
5

Answer 1

@ARMYRANGERS , @eliassaab

Answer 2

This looks like a proportion question, do you know how to cross multiply?

Answer 3

\[4/14 = x/76\]

Answer 4

I dont understand

Answer 5

Okay, so Theo takes 14 random batteries out of 76 total, and finds out that 4 don't work.

Answer 6

That means 4/14 don't work

Answer 7

ok

Answer 8

So if 4 out of 14 don't work, we have to find how many out of 76 won't either.

Answer 9

Both of these are proportional to each other, so 4/14 = x/76

Answer 10

ok

Answer 11

I'm trying to draw the numbers over each other so the next part will be easier

Answer 12

All we have to do is find x, do you know what cross multiplying is?

Answer 13

i forgot how to

Answer 14

Okay

Answer 15

we have to multiply diagonally like this

Answer 16

And we should get:

\[304 = 14x\]

Answer 17

Is this how