Quick sell outlet sold a total of 40 televisions, each of which was either a model p television or a model q television. each model p television sold for $p and each model q television sold for $q. the average (arithmetic mean) selling price of the 40 televisions was $141. how many of the 40 televisions were model p televisions? (1) the model p televisions sold for $30 less than the model q televisions. (2) either p = 120 or q = 120.

12 Model P televisions

28 Model Q televisons.

Step-by-step explanation:

Let be the number of Model P sold and the number of Model Q sold. This problem has 4 unknown variables. With the information on the problem you can write some equations:

The total of television sold was 40:

The average of the selling price was $141:

The Model P sold for $30 less than the other model:

With only three equation, is needed to test them with q=120 and p=120

if

Solving the system of equation by the method of elimination (Multiply this equation by -3):

Substitute the value of in one of the equations:

With a greater than 40 and a negative value of , this can't be the solution.

if

Solving the system of equation by the method of elimination (Multiply this equation by -3):

Substitute the value of in one of the equations:

They sold 12 Model P televisions and 28 Model Q televisions.