Answer:
6.18% of the class has an exam score of A- or higher.
Step-by-step explanation:
When the distribution is normal, we use 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 question, we have that:

What percentage of the class has an exam score of A- or higher (defined as at least 90)?
This is 1 subtracted by the pvalue of Z when X = 90. So



has a pvalue of 0.9382
1 - 0.9382 = 0.0618
6.18% of the class has an exam score of A- or higher.
Answer:
I think it is ether A are B
Answer:
Option D is correct.
Bimodal (Having two modes)
Step-by-step explanation:
- Symmetric distribution is a situation in which the values of variables occur at regular frequencies, and the mean, median and mode occur at the same point.
- In a negatively skewed distribution, the mean is usually less than the median because the few low scores tend to shift the mean to the left.
- In a positively skewed distribution, the mode is always less than the mean and median.
- A bimodal distribution is a continuous probability distribution with two different modes, that is, two different values with the highest and equal frequencies.
Amount of money collected in the 2-day fundraiser is represented by the following equations:
- 12x + 4y = 152 .................. (i)
- 32x + 12y = 420 .................. (ii)
where x is the cost of a chicken lunch and y is the cost of a vegetarian lunch
Multiplying (i) with 3 and subtracting it from (ii)
36x + 12y - (32x + 12y) = 456 - 420
⇒ 4x = 36
⇒ x = 9
Put value of x in (i)
⇒ 12 × 9 + 4y = 152
⇒ 108 + 4y = 152
⇒ 4y = 44
⇒ y = 11
Hence, cost of the vegetarian meal is 11.
Monday=92
Tuesday=88
Wednesday=87
Thursday=91
Friday=88
There are 88 fish remaining