STAT Logical and Numerical Problem-Solving 3

Question 1

A jar contains 4 red, 6 blue, and 2 green marbles. If one marble is drawn at random, what is the probability it is NOT red?

Accepted Answer

2/3

Answer

Non-red marbles = 6 + 2 = 8 out of 12 total; probability = 8/12 = 2/3.

Question 2

What is the next term in the series: 2, 6, 12, 20, 30, ?

Accepted Answer

42

Answer

The terms are n(n+1) for n = 1,2,3…: the 6th term is 6 × 7 = 42.

Question 3

Train A leaves at 9:00 AM traveling at 60 mph. Train B leaves at 10:00 AM from the same station traveling at 90 mph in the same direction. At what time does Train B overtake Train A?

Accepted Answer

12:00 PM

Answer

After 1 hour Train A is 60 miles ahead; B gains 30 mph, so it takes 60/30 = 2 more hours, catching up at 12:00 PM.

Question 4

Which of the following is logically equivalent to the statement 'If it rains, the game is cancelled'?

Accepted Answer

If the game is not cancelled, it did not rain

Answer

The contrapositive of P → Q is ¬Q → ¬P, which is logically equivalent to the original statement.

Question 5

A number is doubled and then 15 is subtracted, giving 45. What is the original number?

Accepted Answer

25

Answer

2x − 15 = 45 → 2x = 60 → x = 30... wait: solving gives x = 30.

STAT - Special Tertiary Admissions Test Practice Test

STAT - Special Tertiary Admissions Test Practice Test

STAT Logical and Numerical Problem-Solving 3