Alexis thinks of a number.
She multiplies this number by 7 then subtracts 6.
Her answer is 50. What was Alexis's original number?
Alexis's friend thinks of a number.
She then does the following operations:
Multiply by 3, subtract 7, multiply by 2 then add 49 (in that order). She finds that the number she ends up with is 13 times her original number.
What was Alexis's friend's original number?
Change NumbersEasier Questions
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Too difficult? There are some simpler questions like this on the THOAN Starter page.
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Apple iPad Pro
The analytics show that more and more people are accessing Transum Mathematics via an iPad as it is so portable and responsive. The iPad has so many other uses in addition to solving Transum's puzzles and challenges and it would make an excellent gift for anyone.
The redesigned Retina display is as stunning to look at as it is to touch. It all comes with iOS, the world's most advanced mobile operating system. iPad Pro. Everything you want modern computing to be. more...
Before giving an iPad as a Christmas gift you could add a link to iPad Maths to the home screen.
Math with Bad Drawings
I had been tutoring the wonderful Betsy for five years. When the day came for our last ever session together before the end of her Year 13, I received this beautiful book as a gift of appreciation.
This a very readable book by Ben Orlin. I'm really enjoying the humour in the writing and the drawings are great.
Ben Orlin answers maths' three big questions: Why do I need to learn this? When am I ever going to use it? Why is it so hard? The answers come in various forms-cartoons, drawings, jokes, and the stories and insights of an empathetic teacher who believes that mathematics should belong to everyone.
Teacher, do your students have
access to computers?
Here a concise URL for a version of this page without the comments.
Here is the URL which will take them to the Think Of A Number exercise.
Here is the URL which will you to our eQuation Generator which provides unlimited practice solving linear equations.