Challenge: Can you solve this math problem for middle schoolers – without a calculator?
Classic brain training methods are perhaps puzzles like crosswords or sudoku, but I have recently become more attracted to the type of challenge you’ll see below.
These puzzles have been flooding the web lately, probably because they are really fun!
These are old classic mathematical problems. When you were in middle or high school.
These math problems are more fun when you find yourself trying to remember the math you learned as a child.
Can you figure out the correct solution?
Here is the challenge, in the picture below.
At the top of the picture, we see the task and then four possible answers.
Which solution do you think is the correct one?
How did you come up with it?
Take your time and think about it to find the correct solution.
Done? Below you can check if you picked the right number!
A
B
C
The correct answer
The correct answer is B: 12.
Why is 12 the correct answer?
Well, if you remember from your school days, according to the order of operations, you do multiplication before addition and subtraction, so you start by solving 3 x 3, which results in 9.
Then we are left with a simpler math problem: 3 + 9 – 3 + 3
The answer is therefore 12.
Did you pick the correct number? Congratulations!
The Forgotten Tools of Typing: Typewriter Eraser Brushes
The circular objects in the image are typewriter erasers, which came with a small brush attached to them. The erasers themselves were made from soft materials like rubber, often infused with fine abrasives. This combination was designed to remove ink or typewriter ribbon marks from paper, which was the primary method of correcting mistakes on a typed document before the advent of white-out or digital editing.
The small brush on the tool was used to gently whisk away the eraser debris left on the paper after erasing a letter or a word. In an age when typewriters ruled the business and literary worlds, these tools were essential to maintaining neat and professional-looking work.
A Snapshot in Time: When Eraser Brushes Were Essential
In the early to mid-20th century, typewriter eraser brushes were as common as correction fluid or digital backspace keys are today. Every typist had one on their desk because, despite their best efforts, mistakes in typing were inevitable. These tools allowed for correcting those mistakes without the need to retype an entire page.
Back then, carbon paper was often used for making copies, so one mistake could mean fixing multiple sheets of paper. Eraser brushes were gentle enough not to tear the delicate paper yet effective at removing the erroneous marks.
The Decline of the Typewriter Era
With the rise of word processors and eventually personal computers, typewriters quickly became obsolete. The need for such specialized erasers faded as digital text allowed for instantaneous editing. Today, these erasers are rare relics from a time when typing was both an art and a skill.
For those who remember using these eraser brushes, seeing one today is a nostalgic reminder of how much the world of writing and editing has evolved. The phrase “times have changed” has never been truer, especially when comparing the challenges of fixing a typewritten document to the ease of modern technology’s undo button.
A Niche Collectible
Today, typewriter eraser brushes are considered collectibles. Vintage enthusiasts and lovers of retro office supplies value them for their simplicity and effectiveness. Though they might look out of place in a world dominated by digital devices, they serve as a testament to the ingenuity of past generations and the unique tools that once supported everyday tasks.
Conclusion: From Essential to Obsolete
For those who’ve never used a typewriter, the tools in the image may seem mysterious, even obsolete. But for older generations, they bring back memories of the rhythmic clacking of typewriter keys, the smell of ink ribbons, and the ever-present eraser brush sitting nearby. Times have certainly changed, and as with many innovations, what was once essential now rests quietly in history’s archives.
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