Respuesta :
Answer:
The mean of the test is 65
Step-by-step explanation:
Let the mean be x and SD be y
3 SD BELOW the mean means that we are taking away 3 SD FROM the mean
Mathematically, we have that as;
x - 3y = 41 •••••(i)
73 is 1 SD above mean
Mathematically;
x + y = 73 ••••••••(ii)
So let us solve both equations simultaneously
Simply multiply equation ii by 3 then add to i
x - 3y = 41
3x + 3y =219
4x = 41 + 219
4x = 260
x = 260/4
x = 65