The world’s shortest IQ test

First Professor in 2005 Frederick The world’s shortest IQ test is still in use today. According to Shift Delete, this test, also called the Cognitive Reflection Test, consists of only three questions.

Here are the questions

1. A stick and ball costs $1.10. If the stick costs $1.00 more than the ball, how much will the ball cost?
2. If 5 machines produce 5 products in 5 minutes, how long will it take 100 machines to produce 100 products?
3. In a lake covered with water lilies, the flowers are growing to double their size with each passing day. If it takes 48 days for lotus flowers to cover the entire lake, how long will it take to cover half the lake?

Answers

1- Although many people think that the answer is 10 penny, this answer is not correct. The correct answer to the first question is as follows:

If we call the stick x and the stick is $1 more than the ball, it becomes x+1. Therefore, the cost of the stick and ball will be 2x+1. Thanks to the information obtained from the question with the result obtained here, it remains to take action to reach the answer.

2 x + 1 = 1.10 dollars

2x = 1.10 dollars – 1

2x= 0.10 Penny

x= 0.05 Penny

2- Although many people think that the answer is 100, this is not true. If 5 machines can produce 5 pieces of a product that takes 5 minutes to manufacture, then 100 machines can produce 100 products simultaneously, working within 5 minutes.

3- Since many people say half, they divide 48 by two and find the answer as 24 days. But this is not a correct answer either. Because to find the answer here, it is necessary to look at the growth of flowers as a ratio. Whatever the answer, it was half full the day before it was fully covered with flowers. Therefore, the answer is 48-1=47.