A magazine printed photos of three celebrities along with three photos of the celebrities as babies. The baby pictures did not identify the celebrities. Readers were asked to match each celebrity with the correct baby pictures. What is the probability that a reader guessing at random will match all three correctly?
Solution
For the first celebrity, you have a 1/3 chance of picking the photo. Given you get the picture right, you now have a 1/2 chance of picking the next photo. If you get both of them right, you are guarenteed to get the third right. Thus the probability is 1/2*1/3 which is 1/6.
-JasonDaGoat
We will compute each expression.
A)
B)
C)
D)
E)
Ordering these, we get . Out of these, is the largest number and option adds up to . Therefore, the answer is .
- SBose
All of Marcy’s marbles are blue, red, green, or yellow. One third of her marbles are blue, one fourth of them are red, and six of them are green. What is the smallest number of yellow marbles that Marcy could have?
Solution
The 6 green marbles and yellow marbles form 1 - frac{1}{3} - frac{1}{4} = frac{5}{12} of the total marbles. Now, suppose the total number of marbles is x. We know the number of yellow marbles is frac{5}{12}x - 6 and a positive integer. Therefore, 12 must divide x. Trying the smallest multiples of 12 for x, we see that when x = 12, we get there are -1 yellow marbles, which is impossible. However when x = 24, there are frac{5}{12} cdot 24 - 6 = boxed{textbf{(D) }4} yellow marbles, which must be the smallest possible.