







How many marbles does Haley have? 
20161019 

From Pat: Sabrina has 1/4 the marbles as Haley.
They have 305 total. How many marbles does Haley have? Answered by Penny Nom. 





A conditional probability problem 
20150824 

From Faustina.: Please I have an exam tomorrow. And I have tried by best in solving this Question. An urn contains 10 white, 5 yellow and 10 black marble. A marble is chosen at random from the urn and it is noted that it is one of the black marble, what is the probability that it is yellow? Answered by Penny Nom. 





More on marbles in a jar 
20120927 

From josh:
Question from josh, a student:
Suppose you have a jar containing 100 red marbles and 100 white marbles. A) If you draw 5 marbles in a row, throwing each marble across the room as you draw it, what is the probability that at least one of them was red? B) If you draw 101 marbles in a row, throwing each one across the room as you draw it, now what is the probability that at least one of them was red?
I saw that this answer was already answered but "The probability that at least one is red is 1 minus the probability that they are all white." makes no sense to me can you please explain i thought that each time a marble is taken out the amount left is different can you please explain better Answered by Robert Dawson. 





There are 30 marbles in a bag 
20081121 

From Cori: There are 30 marbles in a bag. Twice as many red, as blue, and 1 more green than there are red. What is the probability that when one is pulled out, it will be red? Answered by Penny Nom. 





Probability: Marbles in a jar 
20080922 

From Andrea: Suppose you have a jar containing 100 red marbles and 100 white marbles.
A) If you draw 5 marbles in a row, throwing each marble across as you
draw it, what is the probability that at least one of them was red?
B) If you draw 101 marbles in a row, throwing each one across the room
as you draw it, now what is the probability that at least one of them was
red? Answered by Harley Weston. 





How many marbles are Red and how many marbles are White? 
20070313 

From Angie: A jar has 16 marbles in it. Most of the marbles are Red and the rest are
White. Two marbles are taken out of the jar at the same time. It is
equally probable that two marbles are of the same colour as the two
marbles of different colour (that is the probability that they are both red
or both white is the same as they are different). How many marbles are Red and how many marbles are White?
Could anyone help me with the above question?
Best regards,
Angie Answered by Danny Dyer. 





How many marbles are there? 
20060830 

From Cathey: Four children are playing with marbles. At the end of the day, one child has four less than half the marbles. The second child has six more than onefifth the marbles. The third child has one third of what the first child has and the fourth child has one less than the third child. How many marbles are there? Answered by Stephen La Rocque. 





A bag contains 9 red, 6 white, 3 blue, and 8 green marbles 
20060518 

From Micheael: A bag contains 9 red, 6 white, 3 blue, and 8 green marbles. Two marbles are drawn, but the first marble drawn is not replaced. Find P(white, then white). Make into one reduced fraction. Answered by Paul Betts and Steve La Rocque. 





A hat contains between 10 and 25 marbles 
20060306 

From Kerry: A hat contains between 10 and 25 marbles. Some marbles are green, and the rest are yellow. Without looking you are to reach into the hat and pull out a marble. The probability of pulling out a green marble is 2/9. How many marbles are in the hat and explain? Answered by Stephen La Rocque and Penny Nom. 





A bag contains 6 red marbles,9 blue marbles,5 green marbles. 
20060224 

From Jen: A bag contains 6 red marbles,9 blue marbles,5 green marbles. You withdraw one marble,replace it,and then withdraw another marble. What is the probability that you do not pick two green marbles? Answered by Stephen La Rocque. 





Four marbles on a box 
20040322 

From Karyn: Suppose 2 solid color marbles and 2 striped marbles are placed in a box. All are the same size. If one marble is randomly drawn from the box and replaced, then a second marble is randomly drawn, what is the probability that the marble drawn both times will be striped?
I know there is a simple formula for working this out but I can't remember how.
Answered by Penny Nom. 





Three bags of marbles 
20021108 

From A student: I have 3 bags of marbles 1 bag is labeled blue; 2nd bag is labeled red; 3rd bag is labeled blue & red all the bags are mismarked your job is to take one marble from 1 bag look at it and correctly label all the bags Answered by Penny Nom. 





A bag with 3 red marbles and 
20010927 

From Mike: In a bag, there are 3 red marbles and "B" blue marbles. Two marbles are randomly selected from the bag without replacement. The probability that the two marbles are the same color is 0.5. Calculate the sum of all possible values of B. Answered by Claude Tardif. 





Probability 
19980917 

From Chris: Six marbles are placed in one of three boxes. What is the probability that each box contains two marbles? What is the formula used? Answered by Penny Nom and Chris Fisher. 

