It is time to post the solution to the Cookies, Bananas and Clocks algebra maths puzzle that was posted last month.
If you have not had a go at solving this puzzle and registering your answer on the poll; Stop reading the solution, click on the link above and go do it now. 🙂
The puzzle image is shown below:
Here is the “initial” solution:
- There are three cookies which total 30, so each cookie is 10.
- There are two bananas and one cookie which total 14, take away 10 so each banana is 2.
- There are one banana and two clocks which total 8, take away 2 so each clock is 3.
- The final sum is 3 + 2 + 2 x 10.
- Doing multiplication first gives 3 + 2 + 20.
- So the final answer is 25 …. Which is incorrect.
Look closer at the image and you will notice the following:
- The cookies have chocolate chips on them, so you are counting chips, not cookies.
- There are two bananas in each bunch on the second and third lines.
- The hour hand of the clock has different positions, so you are counting hours not clocks.
- The final equation has a different hour hand position, single bananas and different number of chips.
So let’s start again with the correct solution:
- There are three cookies with 10 chocolate chips each which total 30, so each chip is 1.
- There are four bananas and a cookie with 10 chips which total 14, take away 10 so each banana is 1.
- There are two bananas and two clocks at 3 o’clock which total 8, table away 2 so each hour is 1.
- The clock in the final sum is set to 2 o’clock and the cookie has 7 chocolate chips on it.
- The final sum is 2 + 1 + 1 x 7.
- Doing multiplication first gives 2 + 1 + 7.
- So the final correct answer is 10.
Where you really observant? Did you get it right? At the time of posting the solution, 30% of respondents on the poll were correct, which is not so good. The second most popular response was the initial incorrect answer with 22%.
Keep safe, well and sane.
David
This article was originally posted on http://www.winthropdc.com/blog.