Answer:
Lowest score needed=4.92
Step-by-step explanation:
Using the standard normal distribution table we find the value of standard normal deviate corresponding to area of 15%
For area of 15% we have Z= -1.04
Thus we have

Applying values we get

Thus lowest score needed = 4.92
The first step is to find the CHANGE. This is done by subtracting the two values and taking the absolute value. Next step is to find the ratio of the change to the original and multiplying by 100% to make it a percentage.
So;
a) change = Ι60 - 25Ι = 35.
ratio of change to original = 35:25,
multiplying by 100% will give 35/25 × 100% = 140%.
Hence it is a 140% INCREASE.
b) change = | 30 - 66 | = 36
the ratio is 36:66
multiplying by 100% = 36/66 × 100% = 0.545454... ×100% ≈ 54.5%
Hence it is a 54.5% DECREASE.
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