Of 30 students, 1/3 play sports. Of those who play sports 2/5 play soccer. How many students play soccer?

4

Step-by-step explanation:

1/3 of the 30 students play sports

1/3*30 =10

10 students play sports

2/5 of those who play sports play soccer

2/5*10 = 4

4 students play soccer

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: