SOLUTION: You are building a landscape garden and want to spend no less than $3,000 and no more than $8,000. You need 35 tons of rock, each costs $60 and each tree costs $99. How many trees

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Question 329629: You are building a landscape garden and want to spend no less than $3,000 and no more than $8,000. You need 35 tons of rock, each costs $60 and each tree costs $99. How many trees can you buy out of a budget of $24,000? Show your answer using inequalities.
Also want to map (6,15), what is the y-intercept.

Found 2 solutions by stanbon, Theo:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
You are building a landscape garden and want to spend no less than $3,000 and no more than $8,000.
You need 35 tons of rock, each costs $60 and each tree costs $99.
Show your answer using inequalities.
Also want to map (6,15), what is the y-intercept.
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Let # of trees be "x":
3000 <= 35*60+99x <= 8000
---
900 <= 99x <= 5900
9.09 <= x <= 59.596
---
# of trees is
between 8 and 59
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How many trees can you buy out of a budget of $24,000?
35*60+99x <= 24000
99x <= 21900
x <= 221 when rounded down to a whole number
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Cheers,
Stan H.
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Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
x is what you want to spend.
3000 <= x <= 8000

You need 35 tons of rocks.
Each rock costs $60 and each tree costs $99.

How many trees can you buy out of a budget of $24,000?

You need 35 tons of rocks at $60 a ton.

This means that you need a total of 35 * 60 = $2100 for rocks.

If you spend $3000 on the garden, then the number of trees you can buy would be equal to $3000 - $2100 / $99 = 9.09..... which rounds out to 9 trees.

If you spend $8000 on the garden, then the number of trees you can buy would be equal to $8000 - $2100 / $99 = 59.59..... which rounds out to 59 trees.

Since you do not want to spend less than $3,000 and you do not want to spend more than $8,000 then the fact that you have a budget of $24,000 is irrelevant.

If you spend as little as $3,000, then $21,000 remains as cash available for future projects.

If you spend as much as $8,000, then $16,000 remains as cash available for future projects.

Your formula for the number of trees you can buy would be as follows:

x >= $3000
x <= $8000
budget = $24000
rocks = $60 * 35 = 2100
trees = (x - 2100) / 99 truncated to the nearest integer that is less than that value.

You can graph this as follows:

graph%28600%2C600%2C-1%2C10%2C-10%2C80%2C%281000%2Ax-2100%29%2F99%2C9%2C59%29

On this graph, the value of x is given in thousands.

3 = 3000
8 = 8000

The value of y is the numnber of trees you can buy.

I set y = 9 and y = 59 to show you that these values occur at around x = 3 and x = 8

This means that when x = 3000, 9 trees can be bought.

this also means that when x = 8000, 59 trees can be bought.

You can plot the number of tree you can buy in between by looking at the graph or by solving the equation for any value of x between 3000 and 8000.

The equation used to solve is:

y = (x-2100)/99 truncated to the nearest integer smaller than or equal to y.

For example:

When x = 5000, the equation becomes:

y = (5000 - 2100) / 99 = 29.29..... which truncates to 29.

Look on the graph and you will see that when y = 29, the value of x is somewhere around 5.

Here's the graph again, with the value of y = 29 shown.

graph%28600%2C600%2C-1%2C10%2C-10%2C80%2C%281000%2Ax-2100%29%2F99%2C29%29

In these graphs, the value of x below 3 and above 8 are irrelevant and not to be considered.

The equation for how much money is left in the budget would be:

y = $24000 - x.

In this case y would equal the money that is left in the budget.

The graph for the money that is left in the budget is shown below:

graph%28600%2C600%2C-1%2C10%2C-10%2C30%2C%2824000+-+1000%2Ax%29%2F1000%2C16%2C21%29

In this graph, y represents the amount of money that is left in the budget in thousands of dollars.

$24,000 equals 24 on the graph

In this graph, x represents the amount of money that is spent on the project in thousands of dollars.

$3000 = 3 on the graph
$8000 = 8 on the graph.

The only values of x that are relevant would be the values of x from 3 to 8.

You can see that when x = 3, y = 21 which means that $21,000 is left in the budget after $3000 was spent.

You can also see that when x = 8, y = 16 which means that $16,000 is left in the budget after $8000 was spent.