Answer: 5
Step-by-step explanation:
weekday hours x*2
weekend hours y*10
x+y=26
2x+10y=220
----------------------
x=26-y
2(26-y)+10y=220
52-2y+10y=220
8y=220-52
8y=168
y=168/8
y=21
x=26-21=5
x=5
Answer:
11,18,25
Step-by-step explanation:
add 7
Answer:
By the Empirical Rule, 68% of IQ scores are between 87 and 121
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 = 104
Standard deviation = 17
Using the empirical rule, what percentage of IQ scores are between 87 and 121
87 = 104 - 1*17
So 87 is one standard deviation below the mean
121 = 104 + 1*17
So 121 is one standard deviation above the mean
By the Empirical Rule, 68% of IQ scores are between 87 and 121
1/4
There are 100 pence in a pound, so 2 pounds is 200 pence. 50 is 1/4 of 200.