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2 years ago

3 bananas are to be selected from a group of 9. In how many ways can this be done?

Mathematics

2 answers:

lianna [129]2 years ago

7 0

9C3 =9!/((9-3)!3!) =84 ways

Lyrx [107]2 years ago

7 0

Answer: 84

Step-by-step explanation:

The formula to calculate the number of ways to select x things from n things is given by :-

$^nC_x=\dfra{n!}{{!(n-x)!}$

Now, if 3 bananas are to be selected from a group of 9, then the number of ways will be

$^9C_3=\dfrac{9!}{3!(9-3)!}=\dfrac{9\times8\times7\times6!}{6\times6!}=84$

Hence, the number of ways to select 3 bananas from a group of 9 =84

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8-35. Use your knowledge of polygons to answer the questions below, if possible.

Nataliya [291]

Answer:

(a)I. 13 Sides II. 7 Sides

(b) 4 Sides, Square

(c)x=52 degrees

(d)x=107 degrees

(e)1620 degrees

Step-by-step explanation:

(a)The Sum of the Interior angle of polygon with n sides is derived using the formula: (n-2)180.

I. If the Interior angle is $1980^0$

Then:

$(n-2)180^0=1980^0\\$Divide both sides by 180^0 $ to isolate n$\\n-2=11\\$Add 2 to both sides of the equation\\n-2+2=11+2\\n=13$

The polygon has 13 sides.

II. If the Interior angle is $900^0$

Then:

$(n-2)180^0=900^0\\$Divide both sides by 180^0 $ to isolate n$\\n-2=5\\$Add 2 to both sides of the equation\\n-2+2=5+2\\n=7$

The polygon has 7 sides.

(b)The sum of the exterior angle of a polygon is 360 degrees,

Each exterior angle of a n-sided regular polygon is: $\frac{360^0}{n}$

If the exterior angle of a regular polygon is 90°

Then:

$90\°=\frac{360^0}{n}\\ 90n=360\\n=4$

The regular polygon has 4 sides and it is called a Square.

(c)The Sum of the Interior angle of polygon with n sides is derived using the formula: (n-2)180.

Each Interior angle of a regular n-sided polygon is: $\frac{(n-2)180^0}{n}$

For a pentagon, n=5

Then:

$\frac{(5-2)180^0}{5}=2x+4\\108=2x+4\\108-4=2x\\104=2x\\x=52^0$

(d)The sum of the exterior angle of a polygon is 360 degrees.

If four of the exterior angles of a pentagon are 57, 74, 56, and 66.

Let the fifth angle=x

Then:

$57+74+56+66+x=360^0\\253+x=360\\x=107^0$

(e)The Sum of the Interior angle of polygon with n sides is derived using the formula: (n-2)180.

In an 11-gon., n=11

Therefore, the sum of the interior angle=(11-2)180= $1620^0$

The sum of the interior angle does not change either in a regular or irregular polygon.

3 0

2 years ago

I NEED HELP I’ve been stuck on this for a while now and I don’t get it I tried answering this question many times but I can’t ca

Monica [59]

Substitute each x and the respecting y to the equation

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2 years ago

What is the equation of the axis of symmetry?

Anit [1.1K]

Answer:

x = 1

Step-by-step explanation:

Line of symmetry: x = h,

Where h is the x-coordinate of the vertex

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2 years ago

Moira said, "If a right triangle has one side with a length of 3 units and one side with a length

Dima020 [189]

If the two sides with length 3 and 4 are the two legs, then the missing side, i.e. the hypotenuse, is indeed 5.

But it could also be the case that 4 is the hypotenuse and 3 is one of the legs. In this case, the missing side is the other leg, so we calculate it using

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So, a right triangle with legs $\sqrt{7}$ and 3 has an hypotenuse of 4.

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3 years ago

Simplify. f-1g-1 a. f/g b.g/f c.1/fg d.fg

fiasKO [112]

You can rewrite this equation as "f - g - 1". That's all that I see that you can do with this.

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3 years ago