Problema Solution

Mallie takes 7 dance lessons for $82. The cost for 11 dance lessons will cost $122.

A.) Write an equation to find the cost C for L lessons

B.) How much will Mallie be charged if she went to 15 dance lessons?

C.) How many lessons would Mallie have to attendif she is charged $102?

Answer provided by our tutors

A.) we will assume the equation is linear:


C = aL + b, where a and b are constants


Mallie takes 7 dance lessons for $82.


82 = 7a + b


The cost for 11 dance lessons will cost $122.


122 = 11a + b


by solving the system of equations:


7a + b = 82


11a + b = 122


we find:


a = 10


b = 12


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the equation for the cost is:


C = 10L + 12



B.) How much will Mallie be charged if she went to 15 dance lessons?


L = 15 lessons


C = 10*15 + 12


C = $162


Mallie will be charged $162 for 15 dance lessons.



C.) How many lessons would Mallie have to attend if she is charged $102?


C = $102, we need to find L


102 = 10L + 12


L = (102 - 12)/10


L = 9 lessons


Mallie would have to attend 9 lessons for $102.