The cost would be the same for Justin and Bella if 500 checks are sold, costing about $200.
An equation is an expression that shows the relationship between two or more variables and numbers.
Given the equation for Bella:
c = 0.1n + 150
Where C is the monthly cost for n checks.
For Justin:
1.2 = 3k
k = 0.4
C = 0.4n
To have the same cost:
0.1n + 150 = 0.4n
n = 500
c = 0.4(500) = 200
The cost would be the same for Justin and Bella if 500 checks are sold, costing about $200.
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