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IgorLugansk [536]

3 years ago

13

In a class of 25 students

1 answer:

Rudik [331]3 years ago

4 0

If the mean height of 15 girls is 1.65m, the sum of the girls’ heights is 15×1.65=24.75m.

If the mean height of 10 boys is x metres, the sum of the boys’ heights is 10x m.

The sum of all 25 srudents’ heights is 25×1.682=42.05m.

Therefore, 24.75+10x=42.05, x=(42.05-24.75)/10=1.73m, the mean height of the boys.

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At an electronics store, a smart phone is on sale for 35% off the original price of $679. If you use the store credit card, you

kifflom [539]

Answer:

The final price of the smart phone if you use the store credit card is $339.5

Step-by-step explanation:

Given;

original price of the smart phone = $679

initial discount = 35%

additional discount if you use the store credit card = 15%

total discount of the smart phone if you use the store credit card

= 35% + 15% = 50%

The final price of the smart phone, if you use the store credit card is given as;

P = 0.5 X $679

P = $339.5

Therefore, the final price of the smart phone if you use the store credit card is $339.5

8 0

3 years ago

The curved surface area of a solid<br> cylinder is 660 cm2. what is a curved surface area

boyakko [2]

Answer:it’s ok if your not ok

Step-by-step explanation:

5 0

3 years ago

Find the slope of a line given two or more points (2,4)(5,3)

masha68 [24]

Answer:

-1/3 (can u plz give me the brainliest answer???)

Step-by-step explanation:

change in y over the change in x. (or rise over run).

-1/3

Have a nice day!!!!!!!!!!!

<u>KA</u>

7 0

3 years ago

Read 2 more answers

For for each quadratic function below use method of completing the Square or averaging the x-intercept to write the equation in

lions [1.4K]

We have the expressions:

$f(x)=x^2+6x+15$ $y=x^2-4x+9$ $f(x)=x^2-8x$ $y=x^2+7x-2$

Now, with this we operate as follows:

a)

$f(x)=x^2+6x+15=x^2+6x+9+15-9$ $\Rightarrow(x+3)^2+6$

Then, the axis is x = -3 and the vertex (-3, 6)

b)

$y=x^2-4x+9=x^2-4x+4+9-4$ $\Rightarrow(x-2)^2+5$

Then, the vertex is (2, 5) and the axis is x = 2.

c)

$f(x)=x^2-8x+4-4\Rightarrow(x-2)^2-4$

Then, the vertex is (2, -4) andd the axis is x = 2.

d)

$y=x^2+7x-2=x^2+7x+\frac{49}{4}-2-\frac{49}{4}$ $\Rightarrow(x+\frac{7}{2})^2-\frac{57}{4}$

Then, the vertex is (-7/2, -57/4) and the axis is -7/2.

7 0

1 year ago

11x + 12 = 8x - 9 ... please

Marat540 [252]

Assignment: $\bold{\Solve \ Equation: \ 11x+12=8x-9}$

<><><><><><><>

Answer: $\boxed{\bold{x=-7}}$

<><><><><><><>

Explanation: $\downarrow\downarrow\downarrow$

<><><><><><><>

[ Step One ] Subtract 12 From Both Sides

$\bold{11x+12-12=8x-9-12}$

[ Step Two ] Simplify

$\bold{11x=8x-21}$

[ Step Three ] Subtract 8x From Both Sides

$\bold{11x-8x=8x-21-8x}$

[ Step Four ] Simplify

$\bold{3x=-21}$

[ Step Five ] Divide Both Sides By 3

$\bold{\frac{3x}{3}=\frac{-21}{3}}$

[ Step Six ] Simplify

$\bold{x=-7}$

<><><><><><><>

$\bold{\rightarrow Mordancy \leftarrow}$

4 0

3 years ago

Read 2 more answers