Machines and bottles.

5 machines can make =1,000 / 4 =250 bottles in 1 day

250/5 =50 bottles made by 1 machine in 1 day. Therefore,

1,500 / 50 = 30 machines to make 1,500 bottles in 1 day.

Again with the dimensional analysis:

1000 B / (5 M x 4 D) =  50 Bottles/(Machine-Day)        50 Bottles per Machine-Day

1500 B/ (1 D x 50 B/M-D)  =  30 M     30 Machines required

If 5 machines can make 1,000 bottles in 4 days......they can make 1/4 of this =  250 bottles in one day

So....to make 1500 bottles in one day, we need :

1500/250  * 5  =

6 * 5  =

30  machines

It's settled......30 machines......  a bottle for all the answerers......