MDTP Probability 2

Question 1

A jar has 4 red and 6 blue marbles. One marble is drawn without replacement. What is the probability both draws are red?

Accepted Answer

2/15

Answer

P(red then red) = (4/10) × (3/9) = 12/90 = 2/15.

Question 2

Which value cannot be a probability?

Accepted Answer

1.5

Answer

Probabilities must be between 0 and 1 inclusive; 1.5 exceeds this range.

Question 3

How many different 3-digit combinations can be formed from the digits 1–9 if repetition is allowed?

Accepted Answer

729

Answer

With repetition allowed, there are 9 × 9 × 9 = 9³ = 729 combinations.

Question 4

P(A) = 0.6. What is P(A')?

Accepted Answer

0.4

Answer

The complement rule states P(A') = 1 - P(A) = 1 - 0.6 = 0.4.

Question 5

In how many ways can a committee of 2 be chosen from a group of 6 people?

Accepted Answer

15

Answer

Order doesn't matter, so C(6,2) = 6!/(2!4!) = 15.

MDTP - Mathematics Diagnostic Testing Project Practice Test