You have a collection of coins. If you double the number of coins you have, then add 4, you end up with 28 coins. How many coins did you start with?
Category: Math · Difficulty: hard
Hint: Set up an equation based on the operations described.
Answer
12
Explanation
Let x be the initial number of coins. The equation is 2x + 4 = 28. Solving gives x = 12.
This is a hard math riddle — a tricky one that takes a little thought. The answer is 12.
More Math riddles
- I can illustrate relationships between numbers, often with lines and curves. What am I?
- I can help you identify patterns, often found in a structured list. What am I?
- I am a way to measure change, yet I cannot be touched. What am I?
- I can increase or decrease, but I remain constant in my definition. I can describe a shift in values. What…
- I represent the distance across, yet I am not always straightforward. My nature can often confuse. What am I?
- I take two numbers, subtract one from the other, but always yield a positive result. What am I?
- I am a series that grows by a constant difference each time. What am I?
- I am the total days in a week multiplied by the hours in a day. What am I?