# Solving Applied Problems: Two Equations? problem 1 The St.mark's Community bbq served 250 dinners. A child's plate cost $3.50 and an adult's plate cost $7.00. A total of $1347.50 was collected. How many of each type of plate was served?

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The St.mark's Community bbq served 250 dinners. A child's plate cost $3.50 and an adult's plate cost $7.00. A total of $1347.50 was collected. How many of each type of plate was served?

The St.mark's Community bbq served 250 dinners. A child's plate cost $3.50 and an adult's plate cost $7.00. A total of $1347.50 was collected. How many of each type of plate was served?

##### 1 Answer

Yes, you can build two equations here.

What do you know?

1) you know that in total, 250 diners were served.

So,

What else do you know?

2) The costs for each plates and the total cost. This can be expressed as the following equation:

Now, to solve the linear equation system, I would solve the first one for

For example, you can solve the first equation for

Pluging this in the second equation gives you:

This means that there were

Result: