Answer:
yea its in the book
Step-by-step explanation:
Answer:
C.) In perfect health.
Step-by-step explanation:
Given an average weight of 15kg and a standard deviation of 3kg for children of 4 years. Since the weight is based on a normal Z - distribution of 95% which is mean ± 2(standard deviations)
Mean weight interval is :
15 - 2(3) ; 15 + 2(3)
(9 ; 21) ; this weight interval could be interpreted to mean the normal or perfect weight value.
Therefore, given that the child weighs 12kg
Since, 12 kg falls within in the interval, we can conclude that the child is in perfect health.
Answer:
92 attendees had activity cards
Step-by-step explanation:
Let x be the number of students with activity cards. Then 130-x is the number without, and the total revenue is ...
7x +10(130 -x) = 1024
7x +1300 -10x = 1024 . . . . eliminate parentheses
-3x = -276 . . . . . . . . . . . . . collect terms; subtract 1300
x = 92 . . . . . . divide by 3
92 students with activity cards attended the dance.
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<em>Comment on the solution</em>
Often, you will see such a problem solved using two equations. For example, they might be ...
Let 'a' represent the number with an activity card; 'w' the number without. Then ...
- a+w = 130 . . . . the total number of students
- 7a +10w = 1024 . . . . the revenue from ticket sales
The problem statement asks for the value of 'a', so you want to eliminate w from these equations. You can do that using substitution. Using the first equation to write an expression for w, you have ...
w = 130-a
and making the substitution into the second equation gives ...
7a +10(130 -a) = 1024
This should look a lot like the equation we used above. There, we skipped the extra variable and went straight to the single equation we needed to solve.
Answer: 30 i think 10x3=30
Step-by-step explanation:
