M is directly proportional to r^3 When r = 4, M= 160
b) work out the value of r when m = 540

r=6

Step-by-step explanation:

Proportions

We know M is directly proportional to

This can be written as

Where k is the constant of proportionality which will be determined knowing that when r = 4, M= 160. Substituting in the equation above:

Solving for k:

The equation is:

Now find r when M=540:

Dividing by 2.5:

Taking cube roots:

r=6

$4034.40

the perimeter of the field is the sum of the lengths of the four sides:

47 yd + 158 yd + 47 yd + 158 yd = 410 yd

the cost of 3 ft (1 yd) of fence is 3×$3.28 = $9.84.

so the cost of jake's wood perimeter fance is

(410 yd) × ($9.84 /yd) = $4034.40

hi there!

first we need to find out how much they are adding to each number to make the next number.

ex: 4 + 4 = 8, 8 + 8 = 16, and so on.

so continuing with 32,

32 + 32 = 64

64 + 64 = 128

128 + 128 = 256

256 + 256 = 512

4, 8, 16, 32, 64, 128, 256, 512

the 8th term of the sequence will be 512

hope this ! ~