Answer:
x = 51
Step-by-step explanation:
the mean is calculated as
mean = [tex]\frac{sum}{count}[/tex]
here mean = 11.5 , then
[tex]\frac{12.5-10-7.5 +x}{4}[/tex] = 11.5 ( multiply both sides by 4 to clear the fraction )
- 5 + x = 46 ( add 5 to both sides )
x = 51
