The shaded area is the difference between the area of Circle B and the areas of Circle C and Circle O. That is, those white areas are subtracted from the area of Circle B to get the shaded area.

The formula for the area of a circle is

A = πr²

Using this, we find ...

Circle B area = π(3 cm)² = 9π cm²

Circle C area = Circle O area = π(1 cm)² = π cm²

Then the shaded area is ...

Shaded Area = Circle B area - Circle C area - Circle O area

= (9π cm²) - (π cm²) - (π cm²)

= 7π cm² ≈ 22 cm²

5 0

3 years ago

Four years after opening an account that paid simple interest of 4.25% annually, a depositor withdrew the $2,380 in interest ear

satela [25.4K]

Answer:

Step-by-step explanation:

In order to figure out how much money was left in the account after the interest was withdrawn, we have to first find out how much money was initially deposited to earn that amount of interest! The means to find that initial investment is found in the simple interest formula

prt = I, where

p is the initial investement,

r is the interest rate in decimal form,

t is the time in years, and

I is the interest earned. Notice that we have all those things but the p.

Filling in:

p(.0425)(4) = 2380 and

.17p = 2380 so

p = 14000

That means that 14000 was initially invested. If the depositor withdrew the 2380, then

14000 - 2380 is the amount left in the account, namely, $11620

7 0

3 years ago