Arithmetic sequence homework

[banditohorse]

a few questions ...

25. Write an equation to show how the amount of money in a jar of nickels is related to the number of nickels in the jar. If the jar contains 40 nickels, how much money is this?

(Hint: Define the variables that are used in your equation. Use your equation to to determine how much money is in a jar containing 40 nickels.)

27. Find the first, fourth, and tenth terms of the arithmetic sequence described by the given rule.

A (n) + -3 (n-1)(-2.2)

28. Find the first, fourth, and eighth terms of the sequence.
a(n)=-2X2*-1

29. Evaluate the formula
V-Bh/3 when B=9 inchsquarred and H=32 in ... show your work please

30. Simplify the expression.13[62 ÷ (52 – 42) + 9]

 

[berkeman]

25. Write an equation to show how the amount of money in a jar of nickels is related to the number of nickels in the jar. If the jar contains 40 nickels, how much money is this?

(Hint: Define the variables that are used in your equation. Use your equation to to determine how much money is in a jar containing 40 nickels.)

27. Find the first, fourth, and tenth terms of the arithmetic sequence described by the given rule.

A (n) + -3 (n-1)(-2.2)

28. Find the first, fourth, and eighth terms of the sequence.
a(n)=-2X2*-1

29. Evaluate the formula
V-Bh/3 when B=9 inchsquarred and H=32 in ... show your work please

30. Simplify the expression.13[62 ÷ (52 – 42) + 9]

We do not do your homework for you. You must show your work and efforts at solving the problems, before we can offer any tutorial help.

 

[banditohorse]

well i just figured out 29 and 30 but i don't know how to do the two terms one i don't know the set up or how to do it even if you just would show me wiht a different set of numbers. i also don't under what they ask for 25 its not that i was just the answers its the process i don't know ugh!

 

[VeeEight]

You're questions are written out very poorly and hard to understand.

What is a nickel in terms of money?

For the questions on sequences, try plugging in the required numbers into the formula and see what you get. It is not a difficult process but if you are unsure of your answers, post one of your answers as well as your reasoning for someone to verify them.

 

[banditohorse]

okay i tried number 27 out so here it is
27. Find the first, fourth, and tenth terms of the arithmetic sequence described by the given rule.

A (n) + -3 (n-1)(-2.2)


1st term
A(1) + -3 (1-1)(-2.2)
-3 (0) (-2.2)
-3(-2.2)
6.6
4th Term
A(4) +-3 (4-1)(-2.2)
-3(3)(-2.2)
-3(-6.6)
19.8

10th term
A(10)+ -3 (10-1)(-2.2)
-3(9)(-2.2)
-3(-19.8)
59.4

is this anywhere close to what is needed?

 

[berkeman]

okay i tried number 27 out so here it is
27. Find the first, fourth, and tenth terms of the arithmetic sequence described by the given rule.

A (n) + -3 (n-1)(-2.2)


1st term
A(1) + -3 (1-1)(-2.2)
-3 (0) (-2.2)
-3(-2.2)
6.6
4th Term
A(4) +-3 (4-1)(-2.2)
-3(3)(-2.2)
-3(-6.6)
19.8

10th term
A(10)+ -3 (10-1)(-2.2)
-3(9)(-2.2)
-3(-19.8)
59.4

is this anywhere close to what is needed?

The question as stated doesn't seem to make sense. Should it be:

A (n) = -3 (n-1)(-2.2)

If so, when you put in n=1, the right side is not (-3)*(-2.2). Why not?

 

[banditohorse]

The question as stated doesn't seem to make sense. Should it be:

A (n) = -3 (n-1)(-2.2)

If so, when you put in n=1, the right side is not (-3)*(-2.2). Why not?

it is right the way you wrote it i think i just skipped wrighting it but i don't know whay its not (-3)*(-2.2) its exactly how its written in the book. ugh i am so confused >.<

 

[VeeEight]

You made a mistake simplifying -3 (0) (-2.2)

 

[banditohorse]

i did how?

 

[berkeman]

If you multiply anything by zero, what is the result? Certainly not 6.6

 

[banditohorse]

omg i did a blonde ugh so instead it would be
A(1)=+ -3 (1-1)(-2.2)
-3 (0)(-2.2)
-3 (0)
0
Right?

 

[berkeman]

Much better.

 

[banditohorse]

okay so the first one is okay what about the other two did i do those right?

 

[VeeEight]

They look good to me

 

[banditohorse]

okay for 28 i don't think i did it right but this is what i came up with
28. Find the first, fourth, and eighth terms of the sequence.
a(n)=-2X2^-1

okay that's power to one just to let you know ugh i don't like doing math on the computer ...

1st
A(1)= -2x 2^-1
A(1)= -4
cause two to the first power is two right?
then -2 times 2 is negitive four right?
4th
A(4)= -2x2^-4
A(4)= -2x16
A(4) = -32

8th
A(8)= -2 X2^-8
A(8)= -2 x 256
A(8)= -512

anything like that this one really confused me ! see neither of my teachers taught me this before i started homeschooling and i hit this bump and there is nothing on this!

 

[VeeEight]

I am a little confused by your notation. Should the 'X' in the formula denote multiplication? You should state the question EXACTLY as written.
x¹ = x for any number x, so writing it out that way is a waste of time.
However, x^-1 = 1/x (except when x=0)
So, for example, 2^-1 = 1/2 = 0.5

 

[banditohorse]

yes x is multiplication i couldn't remember that the * was the sign of multiplication i am so sorry

 

[banditohorse]

x does mean multiplication but you totally confused me ...

 

[VeeEight]

So is the function a(n) = (-2)(2^-1) or is it a(n) = (-2)(2^-n)? because while doing the problems you are treating a(n) as the latter.

Also, n^-1 = 1/n

 

[banditohorse]

So is the function a(n) = (-2)(2^-1) or is it a(n) = (-2)(2^-n)? because while doing the problems you are treating a(n) as the latter.

Also, n^-1 = 1/n

it the first one a(n) = (-2)(2^-1)

 

[VeeEight]

You can simplify it: a(n) = (-2)(2^-1) = -2(1/2) = -1
So a(n) = -1 for all values of n

 

[banditohorse]

wait whoa i am so still confused here that made no since to my poor mind

 

[VeeEight]

a(n) is a function of 'n'. Since there is no 'n' term in the function, it is constant. So, using the fact that 2^-1 = 1/2 (that is, one over two), a(n) = (-2)2^-1 = (-1)(2)2^-1 = (-1)(2)(1/2) = (-1)(2/2) = (-1)(1) = (-1).