How do I solve these questions?

Mathematics

1 answer:

PSYCHO15rus [73]3 years ago

4 0

Function rule: a = 20w + 115

Slope: 20

Initial value: 115

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We start with $115 in the account. This is the initial value. Each week we add on $20.

So we add $20 for 1 week

We add 2*20 = $40 for 2 weeks

We add 3*20 = $60 for 3 weeks

etc etc

In general, we add 20*w dollars for w weeks onto 115 to get a = 20w+115

The slope is 20 because this is the rate of change, ie how fast the account grows. It grows 20 dollars per week.

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At an airport, it cost 7 to park for one hour and 5 per hour for each additional hour.Let x represent the number hours parked.wr

kompoz [17]

The cost of parking is an initial cost plus an hourly cost.
The first hour costs $7.
You need a function for the cost of more than 1 hour,
meaning 2, 3, 4, etc. hours.
Each hour after the first hour costs $5.

1 hour: $7
2 hours: $7 + $5                  = 7 + 5 * 1          = 12
3 hours: $7 + $5 + $5          = 7 + 5 * 2          = 17
4 hours: $7 + $5 + $5 + $5 = 7 + 5 * 3          = 22

Notice the pattern above in the middle column.
The number of $5 charges you add is one less than the number of hours.
For 2 hours, you only add one $5 charge.
For 3 hours, you add two $5 charges.

Since the number of hours is x, according to the problem, 1 hour less than the number of hours is x - 1.

The fixed charge is the $7 for the first hour.
Each additional hour is $5, so you multiply 1 less than the number of hours,
x - 1, by 5 and add to 7.

C(x) = 7 + 5(x - 1)

This can be left as it is, or it can be simplified as

C(x) = 7 + 5x - 5

C(x) = 5x + 2

Answer: C(x) = 5x + 2

Check:
For 2 hours: C(2) = 5(2) + 2 = 10 + 2 = 12
For 3 hours: C(3) = 5(3) + 2 = 15 + 2 = 17
For 4 hours: C(3) = 5(4) + 2 = 20 + 2 = 22
Notice that the totals for 2, 3, 4 hours here
are the same as the right column in the table above.

6 0

4 years ago

Ruby has a monthly salary of $1,800 and also earns 6% commission on her sales. If Ruby had $37,000 in sales last month, what wer

Nookie1986 [14]

6% of her $37,000 in sales: 37,000 x 0.06 = 2220

Salary $1,800 + $2,220 (commission) = $4,020

So her total earnings: $4,020

4 0

3 years ago

Read 2 more answers

What is the value of x in 150-35x=45

Annette [7]

Your answer is x = 3 because if you take 150 and subtract it by both sides:
150 - 35x = 45
-150 -150

you have to cross out both 150 and -150, take 45 and subtract 150 which will give you -105.
-35x = -105

take -35 and divide by both sides. Cross out the two -35's. Take -105/-35 which your answer is x = 3. Hopes this helps. :)

~Shadow

7 0

3 years ago

How long will it take for an investment to triple, if interest is compounded continuously at 8%?

maw [93]

Answer:

It will take 14 years before the investment triples

Step-by-step explanation:

Continuous Compounding

Is the mathematical limit that compound interest can reach if it was calculated and reinvested into an account's balance over a theoretically infinite number of periods.

The formula for continuous compounding is derived from the formula for the future value of a compound interest investment:

$FV = PV\cdot e^{i.t}$