Question

Chocolate chip and peanut butter cookies are randomly chosen from a cookie jar and placed onto a plate. The first plate had four chocolate chip cookies and one peanut butter cookie. A second plate was prepared with 2 chocolate chip cookies and P peanut butter cookies. If the total probability of drawing a chocolate chip cookie from the first plate and then the second plate is 8/25, how many peanut butter cookies, P, are on the second plate? PLEASE HELP THIS IS A FORMATIVE I HAVE TO FINISH THIS TEST AT 12:55, AND IT IS 12:29 RIGHT NOW PLEASE HELP <:(

Answer 1

Answer:

3 peanut cookies

Step-by-step explanation:

Given that :

Plate 1:

Number of chocolate chip = 4

Number of peanut butter cookies = 1

Probability of drawing chocolate chip cookies from plate 1 :

Probability =( number of required outcome / Total possible outcomes)

P(chocolate chip) = 4 / 5

Plate 2:

Number of chocolate chip = 2

Number of peanut butter cookies = p

P(chocolate chip) = 2 / (2 + p)

Probability of drawing chocolate chip from plate 1 and then plate 2 = 8/ 25

(4/5) * 2/(2+p) = 8/ 25

8 / (10 + 5p) = 8/ 25

8(10 + 5p) = 8 * 25

80 + 40p = 200

40p = 200 - 80

40p = 120

p = 3