Miguel an 2 of his friends share 7 rice cakes equally.

answer: .64

step-by-step explanation

set up the formula for standard deviation for this set of numbers, then simplify

or

step-by-step explanation:

we need to solve for 'x' the following equation:  

we have that:

⇒

⇒ ⇒

factorizing, we get that:

  ⇒

then, the solutions are: or

nothing extraneous has been found!