Answer:
035
Step-by-step explanation:
193
86
81
87
223
226
151
126
120
76
Y:
163
140
150
179
204
128
73
89
136
145
Using a correlation Coefficient calculator, the correlation Coefficient, r for the data = 0.127
The test statistic :
T = r² / √(1 - r²) / (n - 2)
Sample size, n = 10
Hence,
T = 0.127² / √(1 - 0.127²) / (10 - 2)
T = (0.016129 / 0.3506905)
T = 0.3506905
The value of the test statistic to 2 decimal places is 0.35
First, let us break down 28 hours 36 minutes into minutes.
Number of minutes taken to grade 220 essays = (28 x 60) + 36 = 1680 + 36 = 1716 minutes
Now, we can find the average time taken to grade an essay by dividing the time taken to grade 220 essays by 220.
Average amount of time taken to grade an essay = 
= 7.8 minutes, or 7 minutes and 48 seconds
The discriminante :
b^2-4ac
1^2 - 4 * -2 * -28 = 1 - 224 = -223
When the discriminant (b^2-4ac) is less than 0, the equation had no real solutions.
-223<0, so, 2x^2+x-28 = 0 has no real solutions.
Hope that helps :)
