Answer:
b) Chemistry
Step-by-step explanation:
To compare both scored we need to standardize the scores using the following equation:

Where x is the score, m is the mean and s is the standard deviation. So, 82 on chemistry is equivalent to:

Because the mean of the scores on the chemistry final exam is equal to 75 and the standard deviation is 15
At the same way, 80 on Calculus is equivalent to:

Because the mean of the scores on the calculus final exam is equal to 83 and the standard deviation is 13
Now, we can compare the values. So, taking into account that -0.2308 is lower than 0.4667, we can said that the student do better in Chemistry.
First find LCM (least common denominator) which is 12
so now u have 3/4 x 3= 9/12 and 2/3 x 4 = 8/12
now add 9/12 + 8/12 to get answer
try the rest on your own hope dis helped <span>✌️</span>
1/5 x 100 = 20%
Answer: 20%
What is her bill?
To do this on your own, you round up the amount by 5¢ or 10¢, whichever is closer, and then take 20% of her bill
Remember to put 20% into the calculator as 0.2 and multiply 0.2 by her bill that has been rounded up