Answer:
B is all about addition and multiplication
Calculation for plan A:
Let numbe of months = x
Given that $10 is the monthly fee.
Given that $150 is the joining fee.
Then cost equation for plan A is given by:
A=10x+150
Calculation for plan B:
Let numbe of months = x
Given that $30 is the monthly fee.
Given that $50 is the joining fee.
Then cost equation for plan B is given by:
B=30x+50
Now we have to find on what month will the cumulative costs of the plans be equal.
So we will just set both equations equal to each other
10x+150=30x+50
150-50=30x-10x
100=20x
5=x
Hence it will take 5 months to make cost of both plans equal.
To find the total cost plug x=5 into any of above equations:
A=10x+150=10*5+150=50+150=200
Hence final cost will be $200.
Daniel -- 12 balls
Manuel -- 12 balls × 2 = 24
Kendra -- 24 balls x 2 = 48
12 + 24 + 48 = 84 balls total
