Please try with 5 number-fill problems to help exercise brain

Question 1: 

Please try with 5 number-fill problems to help exercise brain Picture 1

Question 2:

Please try with 5 number-fill problems to help exercise brain Picture 2

Question 3:

Please try with 5 number-fill problems to help exercise brain Picture 3

Question 4:

Please try with 5 number-fill problems to help exercise brain Picture 4

Question 5:

Please try with 5 number-fill problems to help exercise brain Picture 5

Answer

How many answers can you give in 1 minute? Compare your answers with the answers below to see if there are some correct answers.

Question 1:

Please try with 5 number-fill problems to help exercise brain Picture 6

In each circle, a total of three numbers in the blue boxes divided by 4 get the number in the white box. We have:

(12 + 18 + 30) / 4 = 15.

(24 + 32 + 24) / 4 = 20.

(3 + 27 + 18) / 4 = 12.

Question 2:

Please try with 5 number-fill problems to help exercise brain Picture 7

In each row, the first two numbers plus the third number get the last (right) number. We have:

2 x 3 + 4 = 10.

3 x 4 + 8 = 20.

4 x 5 + 16 = 36.

Question 3:

Please try with 5 number-fill problems to help exercise brain Picture 8

Number required is 33.

In each cluster of 3 numbers, the square of the number on the left above minus the square of the number on the right above will get the number below. We have:

9 ^ 2 - 6 ^ 2 = 45.

8 ^ 2 - 5 ^ 2 = 39.

7 ^ 2 - 4 ^ 2 = 33.

Question 4:

Please try with 5 number-fill problems to help exercise brain Picture 9

Each column consists of 2 cells that make up a two-digit number. From left to right, the numbers are the squares of 4, 5, 6, 7, 8 and 9. We have:

16 = 4 ^ 2.

25 = 5 ^ 2.

36 = 6 ^ 2.

49 = 7 ^ 2.

64 = 8 ^ 2.

81 = 9 ^ 2.

Number to fill is 1.

Question 5:

Please try with 5 number-fill problems to help exercise brain Picture 10

In each cluster of 3 numbers, the product of the two numbers above, the total of two numbers, equals the number below. We have:

(5 x 2) + (5 + 2) = 17.

(6 x 3) + (6 + 3) = 27.

(4 x 6) + (4 + 6) = 34.

Number to fill is 34.

David Pac

Update 20 November 2020