Simple Probability Question
Hey, I'm terrible at probability so could you help me answer this question?
A bag contains 6 red balls and some white balls. When a ball is taken from the bag at random,the probability that it is red is 3/5. How many white balls are in the bag?
A bag contains 6 red balls and some white balls. When a ball is taken from the bag at random,the probability that it is red is 3/5. How many white balls are in the bag?
6 red balls are 3/5 of the bag, which equates to 60%. The rest are white balls (40%). This means 4 white balls
Hope this helps, Im awful at explaining things...
okay, so three out of five balls are red this means 2/5 must be white. to work out how many are white we have to work out how many balls we have - we have six red, we divide this by the three and then times it by the five making ten. that's the total amount. now we divide ten by five and times that by two giving us 4.
3 red balls = 2 white balls.
6 red balls = 4 white balls.
3 red balls = 2 white balls.
6 red balls = 4 white balls.
Original post by CraigBackner
Hey, I'm terrible at probability so could you help me answer this question?
A bag contains 6 red balls and some white balls. When a ball is taken from the bag at random,the probability that it is red is 3/5. How many white balls are in the bag?
A bag contains 6 red balls and some white balls. When a ball is taken from the bag at random,the probability that it is red is 3/5. How many white balls are in the bag?
So you know that you'll pick one of the 6 red balls 3/5 times. From that, you can deduce that white ball must be picked 2/5 times. The question is basically asking: 6 is 3/5 of some number. What is 2/5 of that unknown number?
I'm sure you'll agree that 6 is 3/5 ths of 10. Since 2/5 balls are white, there must be 4 white balls. (This is of course assuming they there are only red and white balls in the first place)
Posted from TSR Mobile
Original post by 98matt
So you know that you'll pick one of the 6 red balls 3/5 times. From that, you can deduce that white ball must be picked 2/5 times. The question is basically asking: 6 is 3/5 of some number. What is 2/5 of that unknown number?
I'm sure you'll agree that 6 is 3/5 ths of 10. Since 2/5 balls are white, there must be 4 white balls. (This is of course assuming they there are only red and white balls in the first place)
Posted from TSR Mobile
I'm sure you'll agree that 6 is 3/5 ths of 10. Since 2/5 balls are white, there must be 4 white balls. (This is of course assuming they there are only red and white balls in the first place)
Posted from TSR Mobile
Ohh I understand now. Thanks alot!!
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