(08-13-2015 01:10 AM)Peter Murphy Wrote: Only a numerical answer is required; solvers are free to rotate lines (which sounds like a very neat idea!) or to apply any other solving skills they may bring to bear.

(In 2013, problem 9 asked for the sum of the first 213 odd integers. One hopes that some contestants did this in seconds, on paper, with a trivial calculation at the end.)

But if we can become more competent users of our calculators (or if we can show others how they may do so) by putting them to work even when it's not required, we may want to do so, confirming results obtained more easily by thinking outside the calculator box. Or sleeve, as the case may be.

Peter

Thanks and I agree that these are good exercises to explore. BTW - my idea to rotate the lines might work, but I did it wrong... so far.