Answer:
U = 16 oz
0 = 0.5 oz
Step-by-step explanation:
Use z-table to find z-scores for the percents
z-score for 15% = -1.04
z-score for 90% = 1.28
z = x - U / 0
First equation: -1.04 = 15.48 - U / 0
Second equation: 1.28 = 16.64 - U / 0
Solve first equation for U: U = 1.04 0 + 15.48
Multiply both sides of the second equation by 0: 1.28 0 = 16.64 - U
Substitute the first equation for U into the second equation and solve for 0: 1.28 0 = 16.64 - (1.04 0 + 15.48)
1.28 0 = 16.64 - 1.04 0 - 15.48
2.32 0 = 1.16
0 = 0.5
Substitute the value of 0, 0.5, into the first equation and then solve for U: 1.04 (0.5) + 15.48 = 16