Answer:
56 problems
Step-by-step explanation:
So we already know that the answer is: 56. However, a good help is knowing how to obtain this answer from the data provided.
Tony's quiz had 80 questions
Tony correctly answered 70% of them.
We can always write a percentage amount as a ratio by dividing the amount by 100.
.
This means that for every 100 questions, tony will respond correctly 70.
So, if Toni did a questionnaire of n questions, the amount that will answer correctly is calculated by the following expression:

If
then:

Answer:
Step-by-step explanation:
B:Convert the fractional part only then add it to the whole number.
C : 9 1/2,3π,92/5,91/10
B : √26,5.5,5.8,31/5
B: -7,20/3, 7.1 ,√51 , 6π
C: -π , -√5 , -3/2,-1.03
If you choose 10 swimmers and 4 are Stingrays, you can say that Stingrays make up roughly 40% of the swimmers. If 20 Stingrays make up 40% of all the swimmers, we just have to find what number 20 is 40% of. That’s easy enough by cross multiplication:
20/x = 40/100
20/x = 4/10
20/x = 2/5
x = 50.
Double check by multiplying 50 * 0.4. Since 50 * 0.4 = 20, we know we have the right answer. There are about 50 swimmers on this team.
Answer:
b) 1.34
Step-by-step explanation:
The z score is used to determine the number of standard deviations by which the raw score is above or below the mean. If the z score is positive then the z score is above the mean while for a negative z score implies that it is below the mean. The z score is given by:

For the largest 9%, the score is 100% - 9% = 91% = 0.91
From the normal distribution table, the z score that corresponds to 0.91 is 1.34