Answer: (1) The average price for the items sold during that hour was $1.42 --> 1.30c+1.50bc+b=1.421.30c+1.50bc+b=1.42 --> 8b=12c8b=12c --> cb=23cb=23. Sufficient.
(2) The total price for all the goods sold was $14.20. This statement is a bit trickier: 1.30c+1.50b=14.201.30c+1.50b=14.20 --> 13c+15b=14213c+15b=142. Since c and b must be integers, then we should check whether this equation has one or more than one positive integer solutions: 15b=142−13c15b=142−13c --> 142 minus multiple of 13 must be a multiple of 15: only c=4 and b=6 satisfies the equation, thus cb=46cb=46. Sufficient.
Explanation:
(1)
1.30c+1.50bc+b=1.421.30c+1.50bc+b=1.42
1.30c+1.50b=1.42(c+b)1.30c+1.50b=1.42(c+b)
1.30c+1.50b=1.42c+1.42b1.30c+1.50b=1.42c+1.42b
0.08b=0.12c0.08b=0.12c
cb=0.080.12cb=0.080.12
cb=23cb=23
Sufficient
(2)
1.30c+1.50b=14.201.30c+1.50b=14.20
the only possible solution is:
1.30(4)+1.50(6)=14.201.30(4)+1.50(6)=14.20
Ratio is 4:6 or 2:3
Sufficient
Answer is D