Cognitive Reflection Test Classic Numerical Reasoning Problems 2

Question 1

A bat and a ball cost $1.10 in total. The bat costs $1.00 more than the ball. How much does the ball cost?

Accepted Answer

$0.05

Answer

If the ball is $0.05, the bat is $1.05, totaling $1.10 with the correct $1.00 difference.

Question 2

If 5 machines take 5 minutes to make 5 widgets, how long would 100 machines take to make 100 widgets?

Accepted Answer

5 minutes

Answer

Each machine makes 1 widget in 5 minutes, so 100 machines make 100 widgets in the same 5 minutes.

Question 3

A lily pad patch doubles in size every day and covers the whole lake in 48 days. How long to cover half the lake?

Accepted Answer

47 days

Answer

Since it doubles daily, the lake is half-covered the day before it is fully covered, on day 47.

Question 4

A pencil and eraser cost $1.20 together. The pencil costs $1.00 more than the eraser. What does the eraser cost?

Accepted Answer

$0.10

Answer

The eraser is $0.10 and the pencil is $1.10, giving the $1.00 difference and $1.20 total.

Question 5

If it takes 3 painters 3 hours to paint 3 fences, how long for 9 painters to paint 9 fences?

Accepted Answer

3 hours

Answer

Each painter paints one fence in 3 hours, so 9 painters paint 9 fences in 3 hours.

Cognitive Reflection Test Practice Test