1: (1) suppose you need to rent 48 buses x, and you need to rent 64 buses (x- 1). When you rent 64 passenger cars, there are still (16x-64) seats in the car that are not full (represented by algebra with X).

16x-64 > 0 16x-64 < 32。 (Note: If only one correct inequality is listed, 1 is obtained. )

Solution: 4 < x < 6.

∵x is an integer,

∴x=5.

So we need to rent five 48-seat buses.

(2) The cost of renting 48 buses is 5×250= 1250 yuan.

The cost of renting a 64-seat bus is (5- 1)×300= 1200 yuan.

∵ 1200 < 1250, ∴ It is more economical to rent r4 passenger car.

So it is more economical to rent a 64-seat bus.