All categories

3 years ago

I need help with my little brothers homework?

Mathematics

2 answers:

erik [133]3 years ago

7 0

I only did the first part but maybe later I will solve the rest too. If there are any errors but tell me so I can update the pic.

olya-2409 [2.1K]3 years ago

3 0

2. There is 10 different strings
3. I think you need to draw out the string lengths and then your done :)

You might be interested in

The waking time of a student under common conditions is normally distributed with mean of 30 hours and a standard deviation of 5

Elina [12.6K]

Answer:

If the walking time is greater than or equal to 38.225 hours, than it exceeds 95% probability that is lie in top 5%.

Step-by-step explanation:

We are given the following information in the question:

Mean, μ = 30 hours

Standard Deviation, σ = 5 hours

We are given that the distribution of waking time is a bell shaped distribution that is a normal distribution.

Formula:

$z_{score} = \displaystyle\frac{x-\mu}{\sigma}$

We have to find the value of x such that the probability is 0.95

$P( X < x) = P( z < \displaystyle\frac{x - 30}{5})=0.95$

Calculation the value from standard normal z table, we have,

$\displaystyle\frac{x - 30}{5} = 1.645\\\\x = 38.225$

Thus, if the walking time is greater than or equal to 38.225 hours, than it exceeds 95% probability that is lie in top 5%.

4 0

3 years ago

8 cm<br> 6 cm<br> What is the area

Sonbull [250]

Answer:

48cm

Step-by-step explanation:

8 x 6

7 0

3 years ago

Read 2 more answers

Lupita bought 7 pounds of pretzels at a local wholesaler for $16.80. Her friend Charles bought 5 pounds of pretzels at the super

Galina-37 [17]

Answer:

Charly has the better buy

Step-by-step explanation:

The unit cost is

=16.8/7

=$2.4

Her friend Charles bought 5 pounds of pretzels at the supermarket for $12.75

Unit cost

=12.75/5

=$2.55

Charly got the best deal because the unit cost per item is less than that of the friend

3 0

3 years ago

For what value of k are the roots of the quadratic equation kx (x-2)+6=0 equal?

ser-zykov [4K]

Answer:

$\boxed{\sf k=6}$

Step-by-step explanation:

$\sf kx (x-2)+6=0$

Expand brackets.

$\sf kx^2 -2kx+6=0$

This is in quadratic form.

$\sf ax^2 +bx+c=0$

Since this is for equal roots:

$\sf b^2 -4ac=0$

$\sf a=k\\b=-2k\\c=6$

$\sf (-2k)^2 -4(k)(6)=0$

$\sf 4k^2-24k=0$

$\sf 4k(k-6)=0$

$\sf 4k=0\\k=0$

$\sf k-6=0\\k=6$

Plug k as 0 to check.

$\sf \sf 0x^2 -2(0)x+6=0\\6=0$

False.

So that means k must equal 6.

3 0

3 years ago

4x −3/3 =7 what is x

ratelena [41]

Answer:

x = 6

Step-by-step explanation:

4x - 3 = 7×3

4x - 3 = 21

4x = 21 + 3

4x = 24

x = 6

I hope you understood the explanation!

4 0

3 years ago