$3 + $m = the amount spent on one client since one client receives one band ($3) and one meal kit ($m)
Since there are four clients,
=> 4(3 + m) = 36
Isolating m,
3 + m = 9
m = 6
Therefore, the cost of a meal kit is $6
The cost of two meal kits 6 x 2 = $12
The answer is B
