Alan

You can't have the base larger than the perimeter!!!

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Well spotted geno!

2^(x+1) + 5*2^(x-2) = 104

2^x*(2 + 5/4) = 104

2^x*13/4 = 104

2^x = 104*4/13

2^x = 32

2^x = 2^5

x = 5

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This is what I get, numerically, using MathCad:

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This would be everything below 1.282 standard deviations below the mean.

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Just enter tan(20) in the calculator on the Home page.

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Each cable is 13 ft (because √(5^2 + 12^2) = 13) so total length = 3*13 ft = 39 ft

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Here's a numerical approach:

x ≈ 1.858042273

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cos can only have values between ±1, so this equation has no solution.

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Let A be the weekly allowance

At the end of Monday he had spent A/4 and had 3A/4 left

On Tuesday he spent 3A/8 and since this was half of what he had at the start of Tuesday this must also have been what he had left for the rest of the week.  i.e. He had 3/8 of his weekly allowance for the rest of the week.

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