A bag contains 3 red marbles and 4 blue marbles. A marble is taken at random from the bag and replaced. Another marble is taken from the bag. Work out the probability that the two marbles taken from the bag are the same colour.

Give your answer as a fraction.

25/49

Step-by-step explanation:

probability of red and red is (3/7)(3/7) = 9/49

Probability of blue and blue is (4/7)(4/7) = 16/49

Probability of same color = prob. of red and red or prob. of blue and blue

= 9/49 + 16/49

= 25/49

question: how many people can she serve?

answer: she can serve 16.66666667 people. so she can only give 16 people a complete serving.

question: does she have enough ice cream for her guests?

answer: no. explanation: she only has enough for 16 people to have a full serving. however, she can give a 17th person a partial serving.