## Triangles Tried And Tested

The answer of the last triangle’s missing number is 5. Did you get it right? If not, this is how you work it out. We suggest trial and error trying different mathematical functions to see if it gets you the final answer (the number in the middle of the triangle).

As you may have worked out, the solution is to multiply the left side of the triangle and subtract the middle side. Let’s take the first triangle, left side: 2 x 5 = 10, then subtract this number by the middle length number, 10-2 = 8. This brings you to the middle number of the first triangle. Eureka! You got it.