Answer:
a) Between 74 and 90
b) 81.86% of the scores are between 78 and 90
Step-by-step explanation:
a) According to the Empirical Rule, in a normal distribution, 95% of the data are within 2 standard deviations of the mean. Therefore, the range that 95% of the scores fall in is between 82-4(2)=74 and 82+4(2)=90.
b) The percent of scores that are between 78 and 90 is: normalcdf(lower,upper,μ,σ) = normalcdf(78,90,82,4) = 0.8185946784 ≈ 0.8186, or about 81.86% of the scores.
Answer:
the last one
Step-by-step explanation:
Answer:
2nd
Step-by-step explanation:
Answer:
Step-by-step explanation:
We can create a equation to find out.
since we are finding a number where when multiplied by 1.25(this is the decimal form of the percentage) gives us 25, we know that the number we are finding is less than 25. here is the equation.
1.25(x)=25
divide both sides by 1.25 to get "x" alone.
x= 20