Posted in ask uncle colin, fractions.

Ask Uncle Colin is a chance to ask your burning, possibly embarrassing, maths questions -- and to show off your skills at coming up with clever acronyms. Send your questions to colin@flyingcoloursmaths.co.uk and Uncle Colin will do what he can. Dear Uncle Colin, I'm having trouble cancelling fractions -- in

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Posted in fractions, ninja maths.

A redditor asks: How would I find a good rational approximation to something like $\log_{10}(7)$? The Mathematical Ninja mutters 0.85 under his breath, as a matter of course, reasoning that $\log_{10}(7) \approx \log_{10}\left(\sqrt{ \frac {10^2 }{2} } \right)$, although my calculator says 0.845098, so he's off by about 0.6%. However,

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Posted in fractions.

Ours is not to reason why; just invert and multiply. - Anonymous Rule number one of Fractions club is: do NOT let the Mathematical Ninja hear you talking like that, otherwise you’re not going to have ears to hear rule number two. I mean - that is a way to

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Posted in fractions, reader questions.

A friend asks for REASONS: THAERTTHUGAL n. The smallest named fraction in the ancient Tamil language = 1/2323824530227200000000. — The QI Elves (@qikipedia) April 7, 2014 A who to the what now? A twelve-letter word, a thaerrhugaL, representing a number somewhere in the region of twenty-three ninety-ninths of a sextillionth.

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Posted in algebra, factorising, fractions, quadratics.

Towards the end of a GCSE paper, you're quite frequently asked to simplify an algebraic fraction like: $\frac{4x^2 + 12x - 7}{2x^2 + 5x - 3}$ Hold back the tears, dear students, hold back the tears. These are easier than they look. There's one thing you need to know: algebraic

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Posted in algebra, factorising, fractions, quadratics.

Towards the end of a GCSE paper, you're quite frequently asked to simplify an algebraic fraction like: $\frac{4x^2 + 12x - 7}{2x^2 + 5x - 3}$ Hold back the tears, dear students, hold back the tears. These are easier than they look. There's one thing you need to know: algebraic

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Posted in fractions, ninja maths.

The student stared, blankly, at the sine rule problem in front of him. $\frac{15}{\sin(A)} = \frac{20}{\sin(50^º)}$ "I don't know where to st," he started whining as something flew past his head. He knew better than to turn and look at whatever implement of death and destruction he had dodged. "I

Read More →Doing long division is like going to watch Raith Rovers play: you can force yourself do it, but why would you? I'm not going to show you the long division way. It's too much fuss to set out, and frankly I can't be bothered with it. There's a way I

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Posted in basic maths skills, fractions, reader questions.

A reader asks: "When you're working out an expression, why do you sometimes divide after you multiply, when the BIDMAS rules say D comes before M?" This is exactly the reason I don't like BIDMAS - because it suggests something that simply isn't true (that division is before multiplication and

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Posted in basic maths skills, fractions, reader questions.

A reader asks: "When you're working out an expression, why do you sometimes divide after you multiply, when the BIDMAS rules say D comes before M?" This is exactly the reason I don't like BIDMAS - because it suggests something that simply isn't true (that division is before multiplication and

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