Answer: C
Step-by-step explanation: We see that e is 6 for $2.70 and d is 12 for $6.00. Half of 6 is 3 and 2.70 is less than 3 so the cheapest price can't be d. Then, we have 9 for 3.60. 3.60 divided by 9 is 0.40 per which is cheaper than a (0.42 per) so a and d can't be the cheapest. 3 for 1.38 means 0.46 per which is more expensive than a so it also cannot be b. Now we only have c and e left. We divide 2.70 by 6 and find out that the answer is 0.45 which is also more expensive than a. So, the answer is c.
