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3 years ago

Mary is three times older than seth is. if their ages total 76, how old is mary. Please answer ASAP

Mathematics

1 answer:

DedPeter [7]3 years ago

5 0

Mary = 3x

Seth = X

If we know that Mary is three times older than Seth, we can set this up into an equation.

3x + x = 76

Now, we can simplify on the left side by adding the Xs together.

4x = 76

X = 19

Therefore, Seth is 19 years old and Mary is 57 years old.

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Felix joins a local recreation center to play basketball.The recreation center charges a $20 annual fee, plus an additional $15

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Answer:

11 months

Step-by-step explanation:

185 - 20 = 165

165 ÷ 15 = 11

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2 years ago

In a lottery game, a player picks six numbers from 1 to 21. If the player matches all six numbers, they win 40,000 dollars. Othe

Darina [25.2K]

Answer:

The expected value of this game is -$0.26.

Step-by-step explanation:

Expected value:

Each possible earning/loss multiplied by it's probability.

Probability:

Number of desired outcomes divided by the number of total outcomes.

In this question, the order in which the numbers are chosen is not important. So we use the combinations formula to solve.

Combinations formula:

$C_{n,x}$ is the number of different combinations of x objects from a set of n elements, given by the following formula.

$C_{n,x} = \frac{n!}{x!(n-x)!}$

Probability of winning:

Desired outcomes:

The 6 correct numbers, so $D = 6$

Total outcomes:

6 numbers from a set of 21. So

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Probability:

$p = \frac{1}{54265}$

Expected value

$\frac{1}{54265}$ probability of earning 40,000.

$\frac{54264}{54265}$ probability of losing 1. So

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3 years ago

Geometry: Area... triangles and squares

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Step-by-step explanation:

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2 years ago

The degree of the function f(x) = -(x + 1)2(2x - 3)(x + 2)2 is<br> , and its y-intercept is

Serggg [28]

Answer:

Degree = 5

Y intercept = 12

Step-by-step explanation:

our function is given as

$f(x)=-(x+1)^2 \cdot (2x-3) \cdot (x+2)^2$

in the above polynomial our variable is x and it is being multiplied for 5 times. Hence the probable degree for the above polynomial is 5

In order to find the y intercept , we need to put x=0 in f(x) as y intercept is the point at which the function graphically meets y axis and where x = 0

Hence

$f(0)=-(0+1)^2 \cdot (2(0)-3) \cdot (0+2)^2$

$f(0)=-(1)^2 \cdot (0-3) \cdot (2)^2$

$f(0)=-1 \cdot (-3) \cdot 4$

$f(0)=3 \cdot 4$

$f(0)=3 \times 4$

$f(0)=12$

Hence the y intercept is 12 units

6 0

2 years ago

Square root of 5 + square root of 3 the whole divided by sqaure root of 5 - square root of 3

xxMikexx [17]

Answer:

The answer is 4 + √15 .

Step-by-step explanation:

You have to get rid of surds in the denorminator by multiplying it with the opposite sign :

$\frac{ \sqrt{5} + \sqrt{3} }{ \sqrt{5} - \sqrt{3} }$

$= \frac{ \sqrt{5} + \sqrt{3} }{ \sqrt{5} - \sqrt{3} } \times \frac{ \sqrt{5} + \sqrt{3} }{ \sqrt{5} + \sqrt{3} }$

$= \frac{ {( \sqrt{5} + \sqrt{3} ) }^{2} }{( \sqrt{5} - \sqrt{3} )( \sqrt{5} + \sqrt{3}) }$

$= \frac{ {( \sqrt{5} )}^{2} + 2( \sqrt{5} )( \sqrt{3}) + {( \sqrt{3}) }^{2} }{ {( \sqrt{5}) }^{2} - { (\sqrt{3} )}^{2} }$

$= \frac{5 + 2 \sqrt{15} + 3 }{5 - 3}$

$= \frac{8 + 2 \sqrt{15} }{2}$

$= 4 + \sqrt{15}$

3 0

2 years ago