Amath teacher’s midterm is worth 200 points. the mean of the test is 143 and the standard deviation is 15.7. if the scores have a bell shaped distribution, what percentage of the scores are between 111.6 and 174.4? a. about 99.7% b. about 68% c. about 62.8% d. about 95%

The answer is D: about 95%.

Answer with explanation:

Mean,

Standard Deviation

Total Population = 200

Formula for Z Score and calculation of two Z scores.

Similarly,

So the two values that is , 111.6 and 174.4 , lies 2 standard deviation on left and 2 standard deviation on the right of mean.

→With the Help of Z table, the conclusion can be drawn that, 95 % of Data will lie within two standard deviation that is above and Below the Mean.

Option D: About 95%

x > 1.3

step by step:

8.5−0.9x> 9.8−1.9x

step 1: simplify both sides of the inequality.

−0.9x+8.5> −1.9x+9.8

step 2: add 1.9x to both sides.

−0.9x+8.5+1.9x> −1.9x+9.8+1.9x

1x+8.5> 9.8

step 3: subtract 8.5 from both sides.

1x+8.5−8.5> 9.8−8.5

1x> 1.3

step 4: divide both sides by 1.

1x/1 > 1.3/1

a. is correct