Q&A for How to Do a Cool Calculator Trick

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  • Question
    Are there any other cool calculator tricks?
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    Expert Answer
    You can also find the square of any number that ends in 5. First, take your number without the 5, and multiply it by one higher than that number, then add 25 to that product. For instance, when squaring 35, you would multiply 3 by 4 to get the answer 12, then add 25. The answer is 1225. This trick works because the square of any number ending in 5 will always have a 25 at the end. The rest of the digits can be found by multiplying the leading digits of the number by the number that's one higher.
  • Question
    I tried the Number 7 trick, but the answer is always 1,001. Am I doing things right?
    Community Answer
    You and they have to go through the whole process of dividing their first repeating number by each step, like this: 123123 ÷ 11 = 11,193; then 11,193 ÷ 13 = 861; and finally 861 ÷ 123 = 7.
  • Question
    How can I type "she" in a calculator?
    Community Answer
    345 is "she." Check out the article on How to Write Words With a Calculator for more tips.
  • Question
    What is the use of CE in pocket calculators?
    Community Answer
    CE is clear error - you use it to clear any erroneous computations, such as dividing by zero.
  • Question
    I want to try some tricks involving a calculator and lots of people. How can I do it?
    Community Answer
    Here's what you do. First, get a graphing calculator. Ask for one number from each of the people, and plug it in. Then, tell the audience that you can calculate any number they make into a whole number. Divide by Zero. Bow as the audience applauds!
  • Question
    How can I use a scientific calculator for a trick?
    Community Answer
    It probably won't work very well for writing words, but will work great for math tricks or puzzles.
  • Question
    How do I make a C on the calculator?
    Community Answer
    On a scientific calculator, use the bracket on the left. It works sometimes but not always; sometimes it doesn't make the word look right.
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