Alan

True!

As follows

Try [3, 8)   i.e. open interval on the right.

I'm with Melody on this:

Let the smaller number be n. Then bigger number is n+16, so ratio of bigger to smaller is (n+16)/n, which we can write as 1 + 16/n

This has to equal 1 + 4/7  so we must have 16/n = 4/7

Multiply both sides by 7n to get:  16*7 = 4*n

Divide both sides by 4 to get  16*7/4 = n or n = 28

The larger number is therefore 28 + 16 or 44.

I assume you mean "factor" rather than "fracture"!

You can type   factor(N)   (where N is an integer), or  something like factor(x^2+2x+1) for example, into the input region and then press =

The following should help:

Do these look linear or exponential to you?

I assume you are looking for a compass and straight edge construction.  If so then see below:

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Let number of single women be ws and number of married women be wm (Hence number of men = wm)

We are told:  ws/wm = 2/5

fraction of men:   fm = wm/(ws+2wm) 

Divide numerator and denominator by wm:   fm = 1/(ws/wm + 2), hence fm = 1/(2/5 + 2)  or fm = 5/12

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Like so:

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