What kinda of math is this so i can answer..
:)
First, find the 40% discount.
40% of 195 is 78
195 x 0.40 = 78
Subtract that from 195
195 - 78 = 117
Now, find 66 2/3% of 117, since it is an additional reduction after the original discount.
2/3 = 0.667, so 66 2/3% is 66.667%
117 x 0.66667 = 78.00039
And subtract that from 117
117 - 78.00039 = 38.99961, which in dollars would be $38.99. (hundredths, etc. of a cent are usually just dropped; no rounding involved.)
The discount price would then be $38.99
8,000 x .80= 6,400
8,000-6,400= 1,600
1,600-1,000= 600 that is the amount of tuition she will need to pay each year.
4.83 x 10^-3 can be re-written in standard form by moving the decimal point 3 units to the left: 0.00483.
Note: If you want to be mathematically correct, please write 10^(-3), not 10^-3. If the exponent is +, you don't need the parentheses.
This exponential growth/decay (in this case decay because r<1) of the form:
f=ir^t, f=final value, i=initial value, r=common ratio or "rate", t=time.
Since the population decreases by 4.5% each year the common ratio is:
r=(100-4.5)/100=0.955 so we can say
P(t)=8500(0.955^t)
....
7000=8500(0.955^t)
14/17=(955/1000)^t taking the natural log of both sides
ln(14/17)=t ln(955/1000)
t=ln(14/17)/ln(955/1000)
t≈4.22 years (to nearest hundredth of a year)
Since t is the years since 2010, the population will fall to 7000 in the year (2010+4.22=2014.22, more than four years will have elapsed) 2015.
