Answer:
C
Step-by-step explanation:
Let's find the area of each of the two circles.
First Circle:
The first circle has a diameter of 10 inches. That means the radius is 5 inches. So, its area is:

Second Circle:
The second circle has a diameter twice that of the first. So, the diameter is 20 inches. This means that the radius is 10 inches. Find the area:

Now, find the ratio between them by dividing:

Simplify:

1/4 is the same as 1:4
So, our answer is C :)
Answer:
507,409
Step-by-step explanation:
if every 5 days the number quadruples (x4), and we want to know how many acorns fall after 30 days, we can divide 30 by 5 so we only have to calculate for the amount of time the take to quadruple.
30 ÷ 5 = 6
so we only have to quadruple the acorns 6 times.
if we start off with 124 acorns, this is what it will look like:
Day 0: 124 acorns
Day 5: 124 x 4 = 496 acorns
Day 10: 496 x 4 = 1984 acorns
Day 15: 1984 x 4 = 7936 acorns
etc... until day 30.
Day 30: 507904 acorns
I hope this was helpful :-)
Answer:
see explanation
Step-by-step explanation:
Under a rotation about the origin of 90°
a point (x, y ) → (- y, x ), thus
A(2, 2 ) → A'(- 2, 2 )
B(2, 4 ) → B'(- 4, 2 )
C(4, 6 ) → C'(- 6, 4 )
D(6, 4 ) → D'(- 4, 6 )
E(6, 2 ) → E'(- 2, 6 )
First factor each number
39=3*13
52=4*13
Now find the greatest common factor, which in our case is 13.
Answer: 13