12 divided by 0.2 without a calculator is 60.
There are 2 solutions to this problem. One is that 2.5 is 120% of a number and that 2.5 is 80% of a number.
2.5=1.2x
x=25/12
2.5=0.8x
x=25/8
<h3>
Answer: x = 4</h3>
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Explanation
Let y be the height
We have three right triangles that are all similar. We can form the proportion below to solve for y^2. We don't have to find the value of y itself.
2/y = y/6
2*6 = y*y
12 = y^2
y^2 = 12
Now focus on the smaller triangle on the left. It has legs of 2 and y with hypotenuse x
Use the pythagorean theorem to find x
a^2+b^2 = c^2
2^2+y^2 = x^2
4 + 12 = x^2
x^2 = 16
x = sqrt(16)
x = 4
Since the order of elements doesn't matter, we use the formula for combination as follows.
So the number of ways to choose 2 elements from a set of 4 elements would be
Thus the answer is 6.
