CoolStuffYT

To find the total books, find 15 * 4 / 5.

First do 15*4. Then, divide what you get by 5.

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She spent 1-1/4-1/2 = 1/4 of her time reading a book. She also spent an hour reading a book. So that means if we let x equal the total time, 1/4x=1, so x=4 hours.

Yes, first is D

Sorry, second is not B since points D, L, F are not on the same line.

Collinear means that all points are on the same line.

For example, in the first picture, A-H-B does not work, because if you find where they are, they don't form a straight line.

However, D-L-B is in a straight line, so choice D is correct.

With this info, can you do number 2?

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We can have 0, 1, 2, 3, or 4 toppings.

4 choose 0 is 1

4 choose1 is 4

2 is 6

3 is4

4 is 1.

Addthem up to get 16.

If there are nine types of salad, multiply by 9 to get 144 salads.

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Let's first find the outer shaded region, not the one in the square.

Square is 1cm

Two quarter circles equal pi/2 cm

The big quarter circle is pi cm

So the outer area is pi/2-1 cm

The inner part in the square is a 90 degree sector of a circle with radius 1 minus an isosceles right triangle with side 1 (two of them in total).

pi/4-1/2 times 2 equals pi/2-1

Add them up to get

\(\pi -2\) cm^2.

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4 triangles and one rectangle.

Another similar way as EP

Width = x, Height = y

2x+2y=32

xy=56

So x+y=16

Square it

x^2+y^2+2xy=256

Plug in xy=56

x^2+y^2=144

Diagonal is sqrt of that, so 12.

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First one.

If DG is at most one, we can draw a circle with radius 1 and center D.

We know the circle and triangle will share a 60 degree sector (because equilateral triangles have angle 60 degrees each).

So the area of the sector is pi/6.

The area of the entire equilateral triangle is sqrt3/4*a^2, and since a=3, 9sqrt3/4.

3.8971 is the approx. area of triangle

0.5236 is the approx. area of sector.

So 0.5236/3.8971 is around 0.134356

Or 13.4356%.

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Person A does 1/5 of the job in an hour.

Person B does 1/x of the job in an hour.

A and B do 1/5+1/x of the job in an hour.

1/5+1/x = 1/2.

\(\frac{1}{5}+\frac{1}{x}=\frac{1}{2}\)

\(x=\frac{10}{3}\) hours.

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