Question

Loretta places 20 red tiles in a bag. How many blue tiles must be added to the bag to make the probability of randomly drawing a red tile equal to 1/10?

Answer 1

If the number of blue tiles in the bag is 180, then the probability of randomly drawing a red tile equal to 1/10.

Explanation:

Total number of red tiles in a bag = 20

Let us assume the number of blue tiles in a bag = p

So, the total number of tiles in a bag = Red Tiles + Blue tiles

= 20 + p

Now, let us find the probability of drawing a red tile:

`\textrm{The probability of drawing a red tile} = \frac{\textrm{Total Number of red tiles}}{\textrm{Total Tiles}}\\= (20)/(20 + p)`

But, here the probability of drawing a red tile = 1/10

`\implies (1)/(10)  = (20)/(20+p) \\\implies 20 + p = 200\\\implies p = 200- 20 =  180`

or, p = 180

Hence, if the number of blue tiles in the bag = 180, then the P Picking out a red tile ) is 1/10.