algebra...urgent help
posted by vero .
A bag soccer balls contains 8 balls with black design and 7 balls with red design with no other types of soccer balls. Coach graves reaches into the bag and randomly pulls out two soccer balls.
please check my answer
a) explain these events are either dependent or independent.
i think this is independent because the coach just randomly chooses the ball.
b) what is the propability both of the balls will be the ame design color?
is it 98/15.....


The result of the second reach into the bag depends on the result of the first reach.
For example if the coach pulled a black one first, then for the second there would be 7 black and 7 red.
probability first one black = 8/15
then probability second one black = 7/14
so 8/15 * 7/14 for both black
probability first one not black = 7/15
probability second one not black = 6/14
so 7/15 * 6/14 for both white
add those two.
8/15 * 7/14 + 7/15 * 6/14
= (1/15)(56/14 + 42/14) = (1/15)(98/14)
= 98/210 = 49/105 
Oh, 49/105 = 7/15
Respond to this Question
Similar Questions

math
A bag soccer balls contains 8 balls with black design and 7 balls with red design with no other types of soccer balls. Coach graves reaches into the bag and randomly pulls out two soccer balls. please check my answer a) explain these … 
MATH 12 HELP!
One bag contains 4 white balls and 6 black balls. Another bag contains 8 white balls and 2 black balls. A coin tossed to select a bad, then a ball is randomly selected from that bag. Suppose white ball was drawn. What is the probability … 
MATH HELP!!
There are six balls in the bag. Two are basketballs, three are playground balls, and one is a soccer ball. What is the probability that if you pick one of the balls without looking, it will be a soccer ball? 
Maths
Bag A contains 2 white, 1 black and 3 red balls, Bag B contains 3 white, 2 black and 4 red balls and Bag C contains 4 white, 3 black and 2 red balls. One Bag is chosen at random and 2 balls are drawn at random from that Bag. Of the … 
Math
A bag contains three black balls, four white balls and five red balls. Three balls are removed without replacement. What is the probability of obtaining a one of each colour b at least two red balls ? 
Math
A bag contains 33 balls: 10 blue 11 red and 12 green If a person will select balls at random from the bag without replacement, what is the minimum number of balls needed to be selected in order to be sure that the balls selected include … 
Math
A bag contains 33 balls: 10 blue, 11 red, and 12 green. If a person will select balls at random from the bag without replacement, what is the minimum number of balls that need to be selected in order to be sure that the balls selected … 
Maths
Somebody please solve this A bag contains 5 red balls 4 blue balls and m green balls.Two balls are drawn at random from the bag.If probability of both being green is 1/7,then find m. 
GEOMETRY
from a bag containing 6 white balls, 3 black balls and 13 red balls, two balls are drawn at random. what is the probability that they are both red?