Answer:Store A
Step-by-step explanation:
Given
Store A sells 3 cells phones that cost $165 each and offer 4 th one free
i.e. Effective cost of each cell phone is 
Store B sells each cell phone at
each
clearly, store A provides a better deal than B because the cost of 4 cell phones is less for Store A i.e.

Answer: 20
Step-by-step explanation: Hope this help :D
To begin, let's take a relatively simple example.
Make x the subject of the formula:
4y + 2 = x - 4.
x = 4y + 6.
Make y the subject of the formula.
2y/5 - 3x = 2.
TIP: Remember to put brackets around 2 + 3x because both the 2 and the 3x are being multiplied by 5.
y = 5 + 15x/2.
The correct answer would be A