Answer:
7 years
Step-by-step explanation:
Given that:
Let Richard's age = x
Elder sister's age = 2x
Youngwr sister's age = x - 2
Product of sisters ages = 70
2x * (x - 2) = 70
2x² - 4x = 70
2x² - 4x - 70 = 0
x² - 2x - 35 = 0
x² - 7x + 5x - 35 = 0
x(x - 7) +5(x - 7) = 0
(x - 7) or (x + 5) = 0
x = 7 or x = - 5
X can't be negative
Hence, x = 7
Richard is 7 years
Answer:
Step-by-step explanation:
Answer:
Fewer hours
Step-by-step explanation:
2/3 is a fraction and shows the parts of a whole. This means that 2/3 of last week is fewer than last week. Last week is the whole for example 15 hours. This week will be 2/3 or 2/3*15 = 10 hours. This week will be less than last week.
Answer: 0.50477
Step-by-step explanation:
Given : The sugar content of the syrup is canned peaches is normally distributed.
We assume the can is designed to have standard deviation 
milligrams.
The sampling distribution of the sample variance is chi-square distribution.
Also,The data yields a sample standard deviation of 
milligrams.
Sample size : n= 10
Test statistic for chi-square :
i.e. 
Now, P-value = 
[By using the chi-square distribution table for p-values.]
Hence, the chance of observing the sample standard deviation greater than 4.8 milligrams = 0.50477
