A boy is mowing a rectangular lawn 40ft long and 30ft wide. He has cut all of it except for a rectangle that is 20ft long and 15ft wide. What fractional part of the lawn remains uncut?

1/4

Step-by-step explanation:

Find the area of the full rectangle:

=> 40 x 30 = 1200

Find the area of the uncut part:

=> 20 x 15

=> 300

Make these numbers as a fraction.

=> 300 / 1200

=> 3/12

=> 1/4

So, 1/4 part remains uncut.

1/4 of the lawn is uncut.

Step-by-step explanation:

To find the fractional part of the uncut lawn:

Area of the rectangular lawn = 40 × 30 = 1200 ft²

Area of the uncut lawn = 20 × 15 = 300 ft²

300 ft² out of 1200 ft²:

300/1200 = 1/4

1/4 of the lawn is uncut.

since your problem is x^4 = 81, what you have to undeo is the "to the fourth power" part.

the inverse (opposite operation) of "to the fourth power" is "to the fourth root".

  (x^4) ^ ¼   = 81 ^ ¼  

  81 = 3^4     so (3 ^ 4) ^ ¼   =   3 ^ 1   = 3

by hand: (3 ^ 4) ^ ¼   =   3 ^ (4 x ¼) = 3 ^ 1   = 3   (when you take a power to a power, multiply the exponents.)

or, do it by calculator. one way of finding the fourth root is to use ^ (1/4)

step-by-step explanation:

soo this can be solve by using the formula:

f = p( 1 + i)^ n

where f is the future profit

p is the initial profit

i is the percent increase

n is the number of years

a . f = 30000 ( 1.05)^n

b. f = 30000 ( 1.05)^15

f = $62,368