Answer:
20ln(3)
Step-by-step explanation:
Put 15 for A and solve for t.
15 = 45e^(-.05t)
15/45 = 1/3 = e^(-.05t) . . . . divide by 45
ln(1/3) = -.05t . . . . . . . . . . . take natural logs
20ln(3) = t . . . . . . . . . . . . . . multiply by 20, simplify
It will take 20·ln(3) years for the area to decrease to 15 km^2.
Subtract the thickness of the known piece from the total thickness.
Because they have different denominators rewrite them to have the same.
9/32 x 2 = 18/64
Now you have 33/64 - 18/64 = 15/64
The other piece is 15/64 inch thick.
Answer:
<h2> $430.90</h2>
Step-by-step explanation:
Given that the principal p= $290
rate r= 2.2% 2.2/100 =0.022
time t= 18years
by applying the expression
We have
Hence after 18years the money in the account will be $430.90
the rate for 5 cans for $3.70 is 0.74
the rate for 10 cans for $4.10 is 0.41
so the better buy is 10 cans for $4.10 at sams
