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3 years ago

8.4.9 On or off the line & Practice Problems

Mathematics

1 answer:

Andrews [41]3 years ago

4 0

Answer:

Number of quarters → 15

Number of dimes → 2

Step-by-step explanation:

Let the number of dimes I have = y

And number of quarters = x

Since, I have amount in my pocket = $2

Therefore, 0.10y + 0.25x = 2

100(0.10y + 0.25x) = 100×2

25x + 10y = 200

5x + 2y = 40

2y = -5x + 40

y = -2.5x + 20 ---------(1)

Total number of coins in my pocket = 17

x + y = 17

y = -x + 17 ---------(2)

By using a graphing calculator we can graph these two lines (As attached)

Solution of the given system of equations will be the point of intersection of these lines.

Solution → (2, 15)

Number of quarters → 15

Number of dimes → 2

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7nadin3 [17]

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Explanations:

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4 0

3 years ago

Tim Worker expects Social Security benefits of $937 per month. His wife, Mary, is eligible for a wife's benefit of 50 percent of

Anestetic [448]

Hi there

Mary receive
937×0.5
=468.5

Hope it helps

3 0

3 years ago

Read 2 more answers

How do you do this problem?

Sauron [17]

Answer:

Step-by-step explanation:

Part A

If it is compounded quarterly, the interest of 1.5 must be cut into a quarter of its present size. 1.5 //4 = 0.375 % per quarter.

In addition, the number of times that payment will be received is

4 quarters * 5 years = 20 quarters.

i = principle (1 + 0.375/100) ^20

i = principle (1 + 0.00375)^20

The principle = 4000 dollars.

i = 4000 * (1.00375)^20

i = 4000 * 1.07773

i = 4310.93

So she's tied up 4000 dollars to make 300 dollars.

Part B

I can't really give you an answer to this because I don't know if the 7% is compounded and over what period of time if it is, or if they mean 7% annually. There's a lot of variation in this question. Most people don't take money out of the market, so if it compounded, the formula would be

New Principle = starting amount (1.07)^4

New Principle = 4000 * 1.07^4

New Principle = 5243.18 so she would make about 4 times as much as the 300 she makes if she puts the money in a bond.

=============

If the interest is simple interest

Gain would be 0.07 * 4000 = 280 dollars.

Over four years = 4*280 = 1120 dollars.

You are going to have to ask your teacher what is intended by this question.

6 0

4 years ago

Milan is participating in a 4-day cross-country biking challenge. He biked for 48, 51, and 59 miles on the first three days. How

Ivahew [28]

Answer:

62 miles

Step-by-step explanation:

The formula for average is given as

Sum of values / Number of values

Let x = miles on the last day

Hence

48 + 51 + 59 + x/4 = 55

Cross Multiply

= 158 + x = 220

x = 220 - 158

x = 62

Therefore, he needs to bike 62 miles on the last day so that his average (mean) is 55 miles per day.

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3 years ago

Find the value of x^2+1/x^2 when <br>x-1/x=3

BaLLatris [955]

Answer:

sorry i couldnt help

Step-by-step explanation:

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3 years ago