A New Math's Challenge to Start 2021

 We had a new Math's challenge that we worked on this week. 

How could we equal all the numbers from one to twenty using four 4's. We could use any mathematical sign. We couldn't use three 4's, or even five 4's. We had to restrict ourselves to exactly four 4's.

We got really stuck until Mr. Waller showed us factorial 4's. Factorial 4's are recorded like this 4! 

4! = 4 x 3 x 2 x 1

4!= 24

Here are our answers...

1. 4 - 4 + 4 ÷ 4 = 1

2. (4 ÷4)+(4÷4)= 2

3. (4+4+4) ÷ 4 = 3

4. (4 - 4) x 4 = 0 + 4 = 4

5. (4 x 4) + 4 = 20 ÷ 4 = 5

6 (4 + 4) ÷ 4 = 2 + 4 = 6

7. (44 ÷ 4) - 4 = 7

8. (4 x 4) - (4 + 4) = 8

9. (4 ÷ 4) + (4 + 4) = 9

10. (44 - 4) ÷ 4 = 10

11. (4! + 4!) - 4 = 44 ÷ 4 = 11

12. 4! - (4 + 4 + 4) = 12

13. 4! - (44 ÷ 4) = 13

14. (4! ÷ 4) + (4 + 4) = 14

15. (44 ÷ 4) + 4 = 15

16. 4 + 4 + 4 + 4 = 16

17. (4 ÷ 4) + (4 x 4) = 17

18. (4.4 x 4) = 17.6 + .4 = 18

19. 4! - (4 ÷ 4) = 23 - 4 = 19

20. 4! + 4 - (4 + 4) = 20

After we completed this challenge, we had a go at doing the same thing with five 5's.

Lots of creative problem solving and collaboration took place in this Math's challenge.