You have to use the geometric mean of right triangles here. Your ratio is set up like this:

. That gives you

and that

. To find z in the second part, use the Pythagorean Theorem.

and z = 6. In the third part, the student should have had the length of the hypotenuse as the denominator in the second ratio, which is 8. So your answer there is the second one down. In order to do that last one you need to find the hypotenuse in the triangle that has legs of 4 and 10. Using Pythagorean's theorem we find that that length is

. Now set up your geometric mean:

. Cross multiply to get 4x + 16 = 116 and that 4x = 100. Solve for x to get x = 25
<span>The mathematical formula f(x + 1) = (f(x)) is like an arithmetic progression where the original value is f(x), an = f(x+1) , and d is equal to 1. In thsi case, if a0 is equal to x, then the progression should become x+1, x+2, x+3 and so on until x+n. There is no multiplication involved only addition process/</span>
This has to do with ratios. If the current width is 8 inches and he wants to have it 35in, you must multiply the length by the same amount to keep it proportional.
<h3>
Answer: 7/12</h3>
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Explanation:
There are B = 3+5+4 = 12 marbles total, of which A = 12-5 = 7 are not black. Or you could note that we have A = 3 red + 4 white = 7 marbles that are not black.
The probability of selecting a non-black marble is A/B = 7/12
7/12 = 0.5833 = 58.33% approximately
The answers here would be:
16) c
17) a