Hey Child.
The answer to this is 1 or 7:
To find the range for the number of measures played to satisfy our solution, we must solve for x using s = 80.
Next, we subtract 50 from both sides of the equation.
Next, we divide both sides of the equation by 10
Next, to eliminate the absolute value bars, we will add a ± sign in front of our s value, 3.
Finally, we add 4 to both sides of our equation giving us 4 ± 3 = x
Separating this into two equations, we get 4 - 3 = x and 4 + 3 = x
Therefore, x, the number of measures of music played, must be either 1 or 7.
Hope It Helped!~