According to package A and package B, the call cost is equal, there are
If the (1)A package does not exceed 200 minutes, the cost per minute is 66÷200=0.33 yuan.
If Package B does not exceed 450 minutes, the cost per minute is 96÷450=0.2 1 yuan.
Therefore, if the dialing time specified in the package is not exceeded, then B is more favorable.
(2) When the average call charges of two packages A and B are the same, the discounts are the same, then
(66+0.2 * A)/A =(96+0. 15 * B)/B
96/B-66/A = 0.05(A & gt； 200，B& gt； 450) That is to say
B=96/(0.05+ 66/A)
That is, when B=96/(0.05+ 66/A) is met (because the bottom line of package B is 450 minutes, then A > 404 minutes), the phone bill per minute of package A and package B is the same, that is, the same discount.