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Students are asked to find either the initial production cost, or a gradient, or the break even point from a graph.
They are then asked to determine the profit or loss from the graph for the production of a particular number of units. This number is randomised.

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The graph shows the cost of producing pencils and the revenue raised by selling them.

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{advice}

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When {n} units are sold, from the graph, the revenue (income) is equal to {currency(1*n,'\\\\$','')}, and the costs are equal to {currency(0.5*n+20,'\\\\$','')}.

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profit = income - costs = {currency(1*n,'\\\\$','')} - {currency(0.5*n+20,'\\\\$','')} = {currency(profit,'\\\\$','')}.

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A positive number indicates a profit while a negative number indicates a loss.

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The gradient of the cost line is the cost to make one unit.

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The gradient of the income line is the income received from one unit. This is because gradient = rise over run, which is the incomefrom making $n$ units, divided by $n$, which equals the income from one unit.

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choose between the 4 possible questions.

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{question}

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What is the profit or loss in dollars when {n} pencils are sold?

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Enter a profit as a positive number (for example, 20) but enter loss as a negative number (for example, -20)

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Write down an equation for the cost graph. 

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$c$ represents cost, and $n$ represents the number of pencils made.

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$c = $ [[0]] $\\times n + $ [[1]]

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Write down an equation for the income line. 

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$r$ represents revenue (income), and $n$ represents the number of pencils made.

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$r = $ [[0]] $\\times n$

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What does the cost line gradient represent? 

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What does the income line gradient represent?

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Write down your answers. You can check your answers after you have completed this question by choosing \"reveal solutions\".

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