Solution:
The three powers whose value is greater than 500 and less than 550 can be find by following procedure.
We will solve this problem by Hit and trial method by finding the squares, cubes, fourth power, Fifth Power,...etc. of different natural numbers.
23²= 529
8³ = 8 × 8 × 8 =512
The three powers are →→→Eighth power of 2, Square of 23, and Cube of 8.
Answer:
59 to 66
Step-by-step explanation:
Mean test scores = u = 74.2
Standard Deviation = = 9.6
According to the given data, following is the range of grades:
Grade A: 85% to 100%
Grade B: 55% to 85%
Grade C: 19% to 55%
Grade D: 6% to 19%
Grade F: 0% to 6%
So, the grade D will be given to the students from 6% to 19% scores. We can convert these percentages to numerical limits using the z scores. First we need to to identify the corresponding z scores of these limits.
6% to 19% in decimal form would be 0.06 to 0.19. Corresponding z score for 0.06 is -1.56 and that for 0.19 is -0.88 (From the z table)
The formula for z score is:
For z = -1.56, we get:
For z = -0.88, we get:
Therefore, a numerical limits for a D grade would be from 59 to 66 (rounded to nearest whole numbers)