Expand and simply (x + 3) (x + 5)

A web site was hit 300 times over a period of 15 days Show that over some period of 3 consecutive days, it was hit at least 60 t

marshall27 [118]

Answer:

We will divide the 15 days in five periods of 3 consecutive days each.

Now to solve this we will use the pigeonhole principle.

This states that if (N+1) pigeons occupy N holes, then some hole must have at least 2 pigeons.

So, we have n=300 pigeons and k=5 holes.

$[\frac{n}{k} ]=[\frac{300}{5} ]$

Hence, there is a period of 3 consecutive days in which the website was hit at least 60 times.

6 0

3 years ago

Tim must read 2 books from a list of 7 recommended books for his summer reading program. In how many different ways can Tim choo

Marianna [84]

There are 21 ways Tim choose 2 books from the 7 recommended book

Solution:

Given that Tim must read 2 books from a list of 7 recommended books for his summer reading program

To find: different ways can Tim choose 2 books from the 7 recommended books

This is a combination problem

A combination is a selection of all or part of a set of objects, without regard to the order in which objects are selected

The formula for combinations is:

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

where n represents the number of items, and r represents the number of items being chosen at a time

Here we have to choose 2 books from 7 books

Therefore, n = 7 and r = 2

Substituting values in above formula, we get

$\begin{aligned}&7 C_{2}=\frac{7 !}{2 !(7-2) !}\\\\&7 C_{2}=\frac{7 !}{2 ! \times 5 !}\end{aligned}$

For a number n, the factorial of n can be written as,

$n !=n \times(n-1) \times(n-2) \dots \dots \times 2 \times 1$

Therefore, we get

$7 C_{2}=\frac{7 \times 6 \times 5 \times 4 \times 3 \times 2 \times 1}{2 \times 1 \times 5 \times 4 \times 3 \times 2 \times 1}\\\\7C_2 = 7 \times 3 = 21$

Thus there are 21 ways Tim choose 2 books from the 7 recommended book

7 0

3 years ago

Ivan, a botanist, treated a 2 cm plant with a special growth fertilizer. With this fertilizer,

chubhunter [2.5K]

Answer

poop

jsjeiwowkwkw i siemens iwejwns. die ensue i we diei iyyo i yea ma’am i thank you for picking out the car for me today thank youuu so much for bc thank you for bc hbu had to do my streaks

6 0

3 years ago

What defines a line segment

Stolb23 [73]

A line segment is defined as the set of numbers that is contained in a line between the two endpoints.

4 0

3 years ago

Read 2 more answers

Type the correct answer in each box. Use numerals instead of words. If necessary, use / for the fraction bar(s).

Serggg [28]

Answer:

dont know