Using the rule of 72, t=72/r, how long will it take for the principal to double with an annual compound interest rate of 6%?

12 years

Step-by-step explanation:

r = compound interest rate in percent

t = doubling time in years

t = (72percent years)/(6 percent) = 12 years

As a curious cultural fact, there is a connection between the 72 and the fact that ln(2) = 0.69314718055. The constant is 69.3 for continuous compounding...

area of part 1:

a1=base*height/2=(8+2)*(8-2-2-1)/2=10*3/2=15 ft^2

area of part 2:

a2=length*width=(8+2)*1=10 ft2

area of part 3:

a3=length*width=8*2=16 ft2

total shaded area : a1+a2+a3=41 ft2

total area of the reactangle : a=16*8=128 ft2

total area of the nonshaded region : 128-41=87 ft2

answer: i don't understand. what are the options

step-by-step explanation: