Question 181866
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Let the cost of one donut be <i>d</i> and the cost of one cookie be <i>c</i>.


Then A's purchase is described by:


*[tex \LARGE \text{          }\math 2d + 3c = 330 \text{ cents}]


And B's purchase is described by:


*[tex \LARGE \text{          }\math 5d + 2c = 495 \text{ cents}]


Note the change from expressing the cost in dollars to expressing the cost in cents -- that gets rid of the decimal fractions and makes things neater.


Solve the system of two equations for the values of <i>d</i> and <i>c</i> remembering that the answers will come out in cents which you can convert back to decimal parts of a dollar if you wish.


Hint:  Solve by the elimination method.  Multiply the first equation by 2 and the second by -3 to eliminate the <i>c</i> variable.



John
*[tex \LARGE e^{i\pi} + 1 = 0]
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