You unlock this after your 13th stamp, so it takes a while. It's just as well, this is a challenge. You are shown two sets of calculations at the top of the page, say

1 + 4 + 8

What they want you to do is do the first pair - 1+4 = 5. Then do the second pair - 4+8=12. Now they want you to do SOMETHING to those 2 result numbers. They'll show you that below, either a + or -. So say it's a +, you add 5 + 12 and you write down 17. All you write is that final result.

Sometimes the result is negative, but you NEVER write the negative sign. They will put it in for you if the result is negative. All you do is write the actual number. So if the result is -8, they will show the - on the screen for you and you just write in 8.

You unlock the hard mode for this at 17 stamps, which gives you 3 numbers to start with.

If you miss a calculation here, you get a **20 second penalty** so it's well worth it to double check your math before writing in something.

My top score here is 38 seconds

Random speeds:
37 - jet speed
39 - jet speed

Brain Age Walkthrough


Brain Age Review