The lowest score is 9.26 * 4-9.38 * 3 = 37.04-28.5438+04 = 8.9.

2. if there are x oranges, there are 2x apples, and the number of people is y.

The following formula can be listed from the title: 3 * y+4 = X.

7*y-5=2x

The solution is x=43.

y= 13

3. The inlet velocity of pipe A is 1200/9.

The water inflow rate of pipe B is1200/10 =120.

Suppose the original water is x liters.

The speed of drainage is y.

Then you can get it

3y-3*( 1200/9)=x

5y-3 *( 1200/9+ 120)= x

The solution is x= 140.

y= 180