Can You Solve This Math Riddle Without Pen and Paper? A Fun Brain Challenge

Here’s what each step actually adds up to:

1,000 + 40 = 1,040
1,040 + 1,000 = 2,040
2,040 + 30 = 2,070
2,070 + 1,000 = 3,070
3,070 + 20 = 3,090
3,090 + 1,000 = 4,090
4,090 + 10 = 4,100
The correct answer is: 4,100 — not 5,000!

Why Do So Many People Get It Wrong?
At first glance, most people see the repeated “+1000” steps and their brain automatically rounds up the total.

Our minds like patterns and shortcuts — which usually help us in everyday thinking — but in this case, the psychology of expectations misleads us.

When you see the sequence:

+40
+1,000
+30
+1,000
+20
+1,000
+10
Your brain tends to focus on the thousands first and assumes the smaller numbers must total up to another thousand, even though they don’t.

That split-second assumption is why 5,000 is such a common — yet incorrect — answer.

A Valuable Mental Tip

Continued on next page:

Here’s what each step actually adds up to:

1,000 + 40 = 1,040
1,040 + 1,000 = 2,040
2,040 + 30 = 2,070
2,070 + 1,000 = 3,070
3,070 + 20 = 3,090
3,090 + 1,000 = 4,090
4,090 + 10 = 4,100
The correct answer is: 4,100 — not 5,000!

Why Do So Many People Get It Wrong?
At first glance, most people see the repeated “+1000” steps and their brain automatically rounds up the total.

Our minds like patterns and shortcuts — which usually help us in everyday thinking — but in this case, the psychology of expectations misleads us.

When you see the sequence:

+40
+1,000
+30
+1,000
+20
+1,000
+10
Your brain tends to focus on the thousands first and assumes the smaller numbers must total up to another thousand, even though they don’t.

That split-second assumption is why 5,000 is such a common — yet incorrect — answer.

A Valuable Mental Tip

Continued on next page: