Math :( PLEASE HELP?

Question

(tiles)

Draw 20 tiles so that 2 out of 10 are are white and rest shadded. How many white how many shaded

add white tiles so 2 out of 5 are white
How many in all

imagine 48 tiles. if 4 out of 12 tiles are white how many tiles are white.

There are 24 soccer players on the team. Two out of every 3 players have not scored a goal yet this year, How many players have scored goals this year.

For every 8 spelling tests justine took she earned 12 perfect scores this year how many tests did she take.

Answer 1

(a) How many white tiles in 20, if 2/10 are white?

You have this equation of ratios:

2/10 = x/20

Cross-multiply and solve:
10*x = 2*20
4 = x

So you have 20 tiles of which 4 are white.

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(b) Add white tiles so 2 out of 5 are white.

We have 4 white out of 20. If we add 1 white tile, we'd have 5 out of 21, and so on. So let's solve the equation for adding "w" white tiles to yield a 2/5 ratio:

(4+w)/(20+w) = 2/5
5(4+w) = 2(20+w)
20 + 5w = 40 + 2w
3w = 20
w = 20/3 = 6 + 2/3

That seems off -- it's the right answer but they almost certainly don't want fractional tiles. Perhaps they mean REPLACE tiles so that you still have 20 total. If 2/5 are white, you'd need:

2/5 = x/20
5x = 2*20
x = 8

... so you'd have to change 4 additional tiles to white, having 8 white tiles out of 20 total, in order to move the ratio to 2/5.

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(c) How many tiles out of 48 are white, if 4 out of 12 are white?

Another equation of ratios:

x/48 = 4/12
12*x = 4*48
x = 16

There are 16 white tiles out of 48 total, to have a 4/12 ratio.

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(d) 2/3 have not scored goals, so 1/3 have. How many players out of 24 is that?

x/24 = 1/3
3x = 24
x = 8

8 players have scored goals so far.

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(e) Something must be misstated in this problem or missing. It should be something like:

"For every 8 spelling tests justine took she earned [2 PERFECT SCORES. SHE EARNED] 12 perfect scores this year how many tests did she take."

Assuming that's it, it would be:

2/8 = 12/x
2x = 12*8
x = 48

48 tests

Answer 2

really all that this is about is division- sort of. ok here they are

1.Draw 20 tiles so that 2 out of 10 are are white and rest shadded. How many white how many shaded
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- first you need to find out if 10 can go into 20 (and it can 2 times) so you need to times both the numerator and the denominator by 2. So the answer would be there are 4 squares white and 16 shaded. To the second part of your question- since there are already 4 squares that are white, you need to find out how many times 5 goes into 20 (4 times) and then multiply the numerator and the denominator of the fraction (2/5) by four and then you get 8/20- and since there are already 4 squares white- you need to get 4 more that are white.

2. imagine 48 tiles. if 4 out of 12 tiles are white how many tiles are white.
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The same task applies to this problem too- you need to find out how many times 12 goes into 48 (4 times) so you multiply the numerator and the denominator of the fraction 4/12 by four and so you get 16/48 so there are 16 tiles that are white.

3. There are 24 soccer players on the team. Two out of every 3 players have not scored a goal yet this year, How many players have scored goals this year.
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-once again you have to find out how many times 3 goes into 34 (8 times) so you multiply the numerator and the denominator of the fraction 2/3 by 8- and you get 16/24. and since that fraction represents how many players who havent scored a goal- you have to subtract 16 from 24- and you would get 8- so 8 players have scored goals this year.

4. For every 8 spelling tests justine took she earned 12 perfect scores this year how many tests did she take.
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- I'm not sure they gave you enough information- and im not sure about this one- but i think she took 20 tests- i have no clue how i got that. Ask your parents/friends about this one.

-but i hope i helped on the others!

Answer 3

15

Answer 4

4 white and 16 shaded

28

16

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