Bunuel wrote:
If each of the stamps Carla bought cost 20, 25, or 30 cents and she bought at least one of each denomination, what is the number of 25-cent stamps that she bought?
(1) She spent a total of $1.45 for stamps.
(2) She bought exactly 6 stamps.
DS20441
Total Money spent = 20a + 25 b + 30c
Question: b = ?STatement 1: 20a + 25 b + 30cWe know, a, b and c have min value = 1
If we take our price of one stamp of each type
total money spen on them = 20+25+30 = 75 cents
Remaining money = 145 - 75 = 70
Which can be distributed as 20-20-30 or 20-25-25 ii.e. different values of b hence
NOT SUFFICIENTSTatetement 2: a+b+c = 6i.e. {a, b, c} will be {2, 2, 2} or
{1, 2, 3} not in this order essentially hence
NOT SUFFICIENTCombining the statements{2, 2, 2} is NOT possible as total money spent won't be 145 cents in that case
i.e. One possible choice is a = 2, b = 3, c = 1
Second possible choice is a = 3, b = 1, c = 2
NOT SUFFICIENTAnswer: Option E
I don't get why we CAN distribute 20 for instance to 25y (see highlighted part above) if y has to be an INTEGER. Can you explain?
Your life will be defined by the level of effort you tolerate from yourself