Lets get all the information we need first.
A week has 7 days, you practice 30 min each day, so in a week you will practice a total time t of 30 min for 7 times, that is:
t = 7day(30 min/day)
t = 210 min
So in a week you will practice a total of 210 minutes.
Answer:
13.13
Step-by-step explanation:
5.25 x 100/40 is 13.125 which rounds up to 13.13
1.
If no changes are made, the school has a revenue of :
625*400$/student=250,000$
2.
Assume that the school decides to reduce n*20$.
This means that there will be an increase of 50n students.
Thus there are 625 + 50n students, each paying 400-20n dollars.
The revenue is:
(625 + 50n)*(400-20n)=12.5(50+n)*20(20-n)=250(n+50)(20-n)
3.
check the options that we have,
a fee of $380 means that n=1, thus
250(n+50)(20-n)=250(1+50)(20-1)=242,250 ($)
a fee of $320 means that n=4, thus
250(n+50)(20-n)=250(4+50)(20-4)=216,000 ($)
the other options cannot be considered since neither 400-275, nor 400-325 are multiples of 20.
Conclusion, neither of the possible choices should be applied, since they will reduce the revenue.
