Welcome back to another quick brain challenge!

Take a close look at the balance scale. It is perfectly level, which means both sides weigh exactly the same.

On the left side, there are 3 red balls and a 4 kg weight.
On the right side, there is 1 red ball and a 10 kg weight.

The question is simple: How much does each red ball weigh?

Most people overthink this puzzle, but the trick is easier than it looks.

Since the scale is balanced, both sides must have equal weight.

3 balls + 4 kg = 1 ball + 10 kg

Now remove one red ball from both sides. The balance stays equal.

That leaves:

2 balls + 4 kg = 10 kg

Subtract 4 kg from both sides:

2 balls = 6 kg

Now divide by 2:

1 ball = 3 kg

Answer: Each red ball weighs 3 kg.

Quick check:

• Left side: 3 × 3 = 9 kg, and 9 + 4 = 13 kg
• Right side: 3 + 10 = 13 kg

Both sides match perfectly, so the answer is correct.

Did you solve it before reading the explanation?
Comment your answer below and challenge a friend who loves math puzzles!