Answer:
0.13% of students have scored less than 45 points
Step-by-step explanation:
Problems of normally distributed samples can be solved using the z-score formula.
In a set with mean 
and standard deviation 
, the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:
About what percent of students have scored less than 45 points?
This is the pvalue of Z when X = 45. So
has a pvalue of 0.0013
0.13% of students have scored less than 45 points
To find how many sixth graders there are we need to find out how many students there are in 1/5 in the school. Divide 200 by 2 to find 1/5 of the school.
Since 3/5 of the school is 6th graders we multiply 100 by 3 to find that there are 300 students in the 6th grade.
Answer:
5/2 = 2 1/2
Step-by-step explanation:
There are 2 parts in one half, meaning 2 halves equals 1.
If you have 5 halves, you of course would get an improper fraction.
To find the answer, dive the numerator by the denominator. 5 ÷ 2 gives you 2.5, or 2 1/2.
Think about it this way: How many times does will 2 go in to 5 evenly? Twice. 2 times 2 is 4, leaving you with one left over. Whatever the remainder is, is the numerator for the improper fraction, and the denominator stays the same.
Answer:
ratio: 104:1875
Step-by-step explanation:
toy jeep = 12.5 inches
12.5 inches = 1.04 feet
real jeep = 18.75 feet
1.04 / 18.75 = 0.055
104:1875
Answer:
y=mx+b is the form to write this equation. M is the slope and B is the y intercept. therefore:
y=4x-9
Step-by-step explanation:
