Volume of water in Tank P after 15 minutes

= 15 x 1.8l
= 27l

27l = 27 x 1000cm³ = 27000cm³

Height of water in the tank

= Volume of water ÷ length of tank ÷ width of tank

= 27000cm³ ÷ 50cm ÷ 30cm
= 18cm



b)



Increase in height of water in Tank P per min

= 18cm ÷ 15min
= 1.2cm per min


6l = 6 x 1000cm³ = 6000cm³

Increase in height of water in Tank Q per minute

= increase in volume of water per minute ÷ length of Tank Q ÷ width of Tank Q

= 6000cm³ per min ÷ 50cm ÷ 40cm
= 3cm per min


So compared to Tank P,

3cm - 1.2cm = 1.8cm
Height of water in Tank Q increases 1.8cm more than in Tank P per minute.

At 10.15am, height of water in Tank P is 18cm, when filling of Tank Q had just started(which is as good as saying the height of water is 0cm. )

So as every minute passes, the difference in the water height between the 2 tanks is getting smaller by 1.8cm


18cm ÷ 1.8cm per minute = 10minutes

10 minutes is needed for height of water in Tank Q to become the same as Tank P.


1015 + 0010 = 1025

It will be 10.25am when the water level is the same.

Thx alot

Welcome. You can check out my comment for your other question about toy cars if you would like an alternative to Vicky's answer