Question 80526
Call n the number of cubic yards that are ordered.  Then to find the cost of just the gravel
you need to multiply the number of cubic yards (n) by $30 per yard.  Therefore, that cost
is {{{30*n}}}. To that cost the dealer will add $50 for delivery.  This will make the total
cost of gravel plus delivery [call it C(n)]:
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{{{C(n) = 30n + 50}}} dollars.
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This is one of the answers you were asked for in the problem.
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Using this equation you can calculate the the cost of 12 delivered cubic yards by replacing 
n with 12. This results in:
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{{{C(12) = 30*12 + 50}}}
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Multiply 30 by 12 and the equation becomes:
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{{{C(12) = 360 + 50 = 410}}} 
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So 12 cubic yards of delivered gravel costs $410.
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Hope this helps you to understand the problem a little more.
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