I found this little gem on Facebook a few months ago. It was from a page promoting their “puzzles”.
Disclaimer: I learned the “old hard math”. To make things confusing it was called “new math” back in the 1970s. Now it is called “old” math. It took me a few minutes to figure out what was going on with the “new easy’ math.
So lets break this down a little and work it out using both the “old hard” math and the “new easy” math
So let’s try this using the “old hard math” or as I call it the “old” new math. We start with 65 multiplied by 35.
First step is to multiply everything by the one’s place. In this case, it is 5.
- 5 times 5 equals 25. Write down 5 and carry the two.
- 6 multiplied by 5 equals 30. Now add the 2 we carried for 32.
- The answer for this step is 325.
The next step is to multiply by the tens place or 3.
- Since we are really multiplying by 30 not 3; write down a 0.
- Multiply 5 by 3. That equals 15. Write down 5 and carry the 1.
- 6 multiplied by 3 is 18. Add the 1 we carried equals 19.
- For this step, we get 1950.
Now add the products from both steps.
- 5 + 0 = 5
- 2 +5 = 7
- 3+9 = 12. Write down 2 carry the 1. So 1 + 1 = 2.
Now lets compare our answer to the original from the puzzle page.
Old Hard Math
Well, that is interesting. So when the owners of that Facebook page simply brought down the 5 it magically became a 6. When I added 5 + 0, I got 5. Hmm!
Now let’s try the new easy math. Maybe We will have better results.
Let’s give this a try.
- 5 x 5 = 25
- 6 x 3 = 18
- So that gives us 1825
Think we may have an issue with the final answer.
- 6 x 5 = 30
- 5 x 3 = 15
- 30+15 = 45
Now to add the products.
- Bring down the 5.
- 2 + 5 = 7
- 18 + 4 = 22
- Our answer is 2275
Maybe we will have better luck with the “new easy math”.
Looks like we have the same issue. The FB people think the answer is 2276 using their much superior “new easy math”. I followed their steps using the methods I was taught in the “old” new math and got 2275. Guess they were never taught the principle of reasonableness. Let’s see if that is a reasonable answer without doing any math. We know that anything multiplied by 5 MUST end with either a 0 or a 5. So, their answer ends with a 6 and is therefore not reasonable or is wrong.
Based on this I’m thinking life in general is puzzling for the owners of that page. Maybe they should invest in some lessons with Kumon or Sylvan. Well, since I am an old Gen-X er I will just stick with “new” math.
The Dee Zone 