Answer:
a=12 b= 19200
Step-by-step explanation:
Steps:
1. Take -x + 2y= 21
2. Add x on both sides
2y= x + 21
3. Divide everything by 2
Y= 1/2x + 10.5
4. Substitute the y in 7x + 2y= -19 for 1/2x + 10.5
7x + 2(1/2x + 10.5)= -19
5. Multiply everything in parentheses
7x + x + 21= -19
8x + 21= -19
6. Subtract 21 on both sides
7. 8x=-40
8. Divide each side be 8
9. Your answer is
X=-5
Answer:
a) 10.6; 48.7; within
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviation of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean = 29.6
Standard deviation = 6.35
"According to the Empirical Rule, the ages of nearly all lead actresses will be between______________and_____________ years.
Nearly all(99.7%) will be within 3 standard deviations from the mean.
So from 29.6 - 3*6.35 = 10.6 years to 29.6 + 3*6.35 = 48.7 years.
Anna was 11-years old, so she was within this range.
So the correct answer is
a) 10.6; 48.7; within