This is an exponential growth/decay problem...
F=Ir^t, F=final value, I=initial value, r=rate, t=time, in this case:
F=I(1.03)^t and they just want to know when F=2I so
2=1.03^t take natural log of both sides...
ln2=t*ln1.03
t=ln2/(ln1.03)
t≈23.45
So it will take approximately 23.45 years for the population to double..
1990+23.45=2013.45
So during the year of 2013 the population will have double from its 1990 level.
Answer:
1 hr, 48 minutes
Step-by-step explanation:
you can create a proportion:
doughnuts/hours = doughnut/hours (h)
1500/9 = 300/h
cross-multiply to get:
1500h = 2700
h = 27/15
h = 1 12/15, which is 1 hr, 48 minutes because 12/15 = 48/60
Answer:
2
Step-by-step explanation:
15x + 16 = 48 - x
16x = 32
x = 2
Plug two in and it fits right in :)
Answer:
{-1, -8}
Step-by-step explanation:
Please enclose "1 - 3x" inside parentheses so the reader will know that you want the square root of all of "1 - 3x".
Squaring both sides of the given equation, we get:
1 - 3x = x^2 + 6x + 9, or x^2 + 6x + 8 + 3x, or
x^2 + 9x + 8 = 0. Factoring, we get: (x + 8)(x + 1) = 0, so that the solutions are {-1, -8}.
