kurt.physics
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I'm pretty sure there was, but i didn't do itrolror88 said:Yea.. I did. I just did odd numbers which ended in 9, starting from 1999. Then divided them by 3.. to find the answer. Didn't take long, it was like the 4th number down, or something like that.
Was there another way to work it out? ie Algebra?
With Q6.. I just used basic algebra.
Its an odd number, so its in the form 2n + 1
It leaves a remainder of 2 when divided by 3
so 3(2n + 1) + 2 = m
It leaves a remainder of 4 when divided by 5
so 5(2n + 1) + 4 = q
or something like that and then you get a diophantine equation (i think). You solve that or some thing....
I am a bit rough on Diophantine equations and all that stuff because i got this book "Problem-Solving Via the AMC" on Wednesday afternoon (the day before the test) and didnt read much that afternoon (tired). The next morning i took it to school and for the first 30 minutes in the morning before the DEAR (start of class) bell rang i was just sifting through it. So that helped me with question 6, but i haven done much Diophantine equations so i could solve it.
I was to lazy to do trial and error or any other method! Although i got Q19 right as soon as i saw that so, yeh (Q19 is circle with square thing inside)