Please help with number 3 please due today

What is the number of terms in this geometric series? 1+2+4...+128

Stella [2.4K]

The answer is : a^2=1 x 2^n-1

To check if it’s correct

a^2= 1 x 2^2-1

a^2 = 1x 2
a^2 = 2

Hope this helps!

5 0

2 years ago

How many ways can a dance instructor send 4 of her 11 students to a summer dance program?

Sedaia [141]

Answer:

d) 330

Step-by-step explanation:

The number of ways can a dance instructor send 4 of her 11 students to summer dance program is C(11 , 4)

That is $11_{C_{4} }$ ways

by using formula $n_{C_{r} } = \frac{n!}{(n-r)!r!}$

now simplification

$11_{C_{4} } = \frac{11!}{(11-4)!4!}$

= $\frac{11X10X9X8X7!}{(7!)4X3X2X1}$

after cancelling 7! and on simplification

= $\frac{11X10X9X8}{4X3X2X1}$

after cancellation we get 330 ways

The number of ways can a dance instructor send 4 of her 11 students to summer dance program is 330

8 0

3 years ago

Find the Y-coordinate of point P that lies 1/3 along segment RS, where R (-7, -2) and S (2, 4).

QveST [7]

Solution:

Given that the point P lies 1/3 along the segment RS as shown below:

To find the y coordinate of the point P, since the point P lies on 1/3 along the segment RS, we have

$\begin{gathered} RP:PS \\ \Rightarrow\frac{1}{3}:\frac{2}{3} \\ thus,\text{ we have} \\ 1:2 \end{gathered}$

Using the section formula expressed as

$[\frac{mx_2+nx_1}{m+n},\frac{my_2+ny_1}{m+n}]$

In this case,

$\begin{gathered} m=1 \\ n=2 \end{gathered}$

where

$\begin{gathered} x_1=-7 \\ y_1=-2 \\ x_2=2 \\ y_2=4 \end{gathered}$

Thus, by substitution, we have

$\begin{gathered} [\frac{1(2)+2(-7)}{1+2},\frac{1(4)+2(-2)}{1+2}] \\ \Rightarrow[\frac{2-14}{3},\frac{4-4}{3}] \\ =[-4,\text{ 0\rbrack} \end{gathered}$

Hence, the y-coordinate of the point P is

$0$

8 0

1 year ago

John wants to find the center of a wall so he can hang a picture. He measures the wall and determines it is 65.25" wide. 65.25"

Viktor [21]

It is given that John wants to find the center of a wall so he can hang a picture. So, John measures the wall and determines it is 65.25 inches wide. Since John has determined that the wall measures a particular amount that means that John has quantified the width of the wall, which in this case comes out to be 65.25 inches.

Again, this is a single number. This means that the width of the wall is a discrete quantity.

Thus, 65.25 inches or 65.25" is a Quantitative and Discrete type of data. Thus, out of the given options, the first option is the correct one.

6 0

3 years ago

A tech company bought a number of computers for its employees: 66 costing \$1600$1600 each, 44 costing \$1200$1200 each, and yy

daser333 [38]

Answer:

5

Step-by-step explanation:

A tech company bought a number of computers for its employees: 6 costing $1600 each, 4 costing $1200 each, and y costing $900 each, where y is a positive odd integer. what is the greatest possible value of y

Solution:

The median of a group of numbers is the middle number when the group of numbers have been arranged either in ascending of descending other. The median of an even group of numbers is the average of the two most middle most numbers while the median of an odd group of numbers is the middle number.

Since there are 6 computers costing $1600, 4 computers costing $1200 each and y computers costing $900 each. Since y is odd, hence y + 6 + 4 would be odd and the median would be the middle number.

Given that the median price = $1200, this means that the middle of the group of numbers is $1200

900, 900, ..., 1200, 1200, 1200, 1200, 1600, 1600, 1600, 1600, 1600, 1600

Since y is odd, for the median price to be $1200, y has to be 3 or 5.

If y = 3:

900, 900, 900, 1200, 1200, 1200, 1200, 1600, 1600, 1600, 1600, 1600, 1600

median = $1200

If y = 5:

900, 900, 900, 900, 900, 1200, 1200, 1200, 1200, 1600, 1600, 1600, 1600, 1600, 1600

Median = $1200

Therefore the greatest possible value of y is 5

5 0

3 years ago