Recall that the average of a given set of numbers is the sum of the numbers divided by the number of numbers.
Therefore, if we want the average to be 82, and we call x the score on Test W, then:
![82=(81+75+88+x)/(4)\text{.}](https://img.qammunity.org/2023/formulas/mathematics/college/ajo7vecfg3wcjus0w1s8i2u0astzdxjges.png)
Multiplying by 4 we get:
![\begin{gathered} 82*4=244+x, \\ 328=244+x\text{.} \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/6czhlx4vdoluvxau163p50n6wbpq1j5mhb.png)
Subtracting 244 from the equation we get:
![\begin{gathered} 328-244=x, \\ x=84. \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/w2dtd2meqozpu7kb5bccpge76p6ns2nqxn.png)
Answer: The recruit must score at least 84 points on Test W.