Question 1113592
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Let x = small soda cost/price), in dollars.

Then the medium soda costs (x+0.7);

     the large  soda costs 2x;

     the jumbo size  costs 2*(x+0.7).


x + (x+0.7) + 2x + 2*(x+0.7) = 9.30

x + x + 0.7 + 2x + 2x + 1.4  = 9.30

6x + 2.1 = 9.30

6x = 9.30 - 2.1 = 7.2  ====>  x = {{{7.2/6}}} = 1.2.


Thus small soda costs 1.2 dollars.  


Based on it, calculate the cost of other sodas on your own.
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<U>The lesson to learn from the solution is THIS:</U>


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    This problem is for one unknown. It is not for 4 unknowns and not for using systems of equations.
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