Working mothers who earn $30,000 or less per year receive a rebate on before and after school care of 75%, plus a school bonus of $6,000 that only applies to this category of earnings. Each dollar
earned above this amount and up to $40,000 reduces the rebate to 55%, and for any amount above
this, the rebate drops to 30%. There are three mothers – Jade earns $40,001, Emily earns $38,000
and Lucy earns $29,550. If the cost of before and after school care is $10,000 per year, what amount
of money does the person have who has the least amount of money left after paying for before and
after school care?

Step-by-step explanation:

12 minutes

Step-by-step explanation:

Since it takes 4 minutes to fill the bathtub with both taps on and stopper is in then for each minute the 2 taps can fill up to a quarter (1/4) of the tub:

Similarly, it takes 6 minutes to drain the tub with both taps off and the stopper is out. This means for each minute the stopper can drain one sixth (1/6) of the tub.

Therefore, when both taps are on and the stopper is out, then for each minutes, the amount of water remaining in the tub is the water flowing in minus the water draining out

So for each minute, one twelveth of the tub is filled, for the tub to be completely filled in, it would take 12 minutes