There are 50 people in a tour group. If you rent a big boat, you can take six people, and the rent is 120. If you rent a boat, you can take four people, and the rent is 100 yuan. How to rent?

First of all, let's see which ship is cheaper, the big ship is 2.25 yuan/person, and the small boat is 2 yuan/person, which means the more ships, the cheaper it is.

If all boats are used, 48 people /6=8 boats, just eight boats can be taken, and the cost is 8* 12=96 yuan, less than 100 yuan.

When the number of small boats is reduced to seven, it is necessary to add 1 large boat, which can accommodate 50 people, and the cost is 7 *12+18 =102 yuan. number

(Because the per capita cost of small boats is low, 2 yuan/person, if the number of small boats continues to decrease and the number of large boats increases, the total cost will be higher than or equal to 102, so there is no need to continue. There is only one way to spend less than 100 yuan, and that is to use all boats. )

If we continue to reduce the number of small boats to six, we need to add two large boats, which can accommodate 52 people and cost 6 *12+2 *18 =108 yuan, which is unacceptable.

If we continue to reduce the number of small boats to five, we need to add three large boats, which can hold 54 people, and the cost is 5 *12+3 *18 =114 yuan. No.

To continue to reduce the number of small boats to four, it is necessary to add three large boats, which can accommodate 48 people, and the cost is 4 *12+3 *18 =102 yuan.

To continue to reduce the number of small boats to three, it is necessary to add four large boats, which can accommodate 50 people, and the cost is 3 *12+4 *18 =108 yuan.

Two small boats and five large boats can accommodate 52 people and cost 1 14 yuan. number

1 small boat, 6 large boats, which can accommodate 54 people. Cost 120 yuan. number

0 small boat, 6 large boats, can accommodate 48 people, and cost 108 yuan. number