Friday, July 31, 2009

Homework Hellllllllllpppp! I don't understand.. Probability?

I need theese answers by 9pm tonight.


Q- You roll a cube which has the numbers 14,17,20,23,24, and 25 on it. You then spin a spinner which has 4 sections. The letters on the spinner are B,J,K,D, and C. P(not C and even )





Q-You roll a number cube numbered from 0-99.


P(a prime number)


Express the probability as a fraction.





Q- You roll a number cube numbered from 1-6.


P(an odd number)


Express the probability as a percent. Round to the neasrest percent.





Q- A jar contains 7 pink, 26 brown, and 13 yellow marbles. A marble is drawn at random.


P(yellow or pink)


Epress the probability as a decimal. Round to the nearest hundreth.

Homework Hellllllllllpppp! I don't understand.. Probability?
1. 1/30


2.1/25


3.1/6, 17%


4.43.47%
Reply:1. I'll assume you meant the spinner has 5 sections since you gave 5 letters it could be. On the cube you have 3 even and 3 odd, so the chance of getting an even number is 3/6 and the chances of not rolling a C is 4/5. So you multiply the two (3/6)*(4/5)=0.40 or 40%





2. From 0-99 the prime numbers are 2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89 97. If you count them up, there are 25 of them. There are 100 faces on the cube, so you have a 25/100 chance of rolling a prime number.





3. There are 3 even and 3 odd numbers on the cube, so you have a 3/6 chance of rolling an odd number. 3/6=0.50 or 50%





4. There are 46 marbles in all. There are 21 pink and yellow marbles. 21/46=0.45652 or rounded to the nearest hundredth is 0.46


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