Answer:
The age of brothers are 4 years and 2 years respectively.
Step-by-step explanation:
We are given that the ages of two brothers have a ratio of 2 to 1. When 4 years have passed, the ratio of their ages will be 8 to 6.
Let the age of the first brother be 'x years' and the age of the second brother be 'y years'.
So, according to the question;
- The first condition states that the ages of two brothers have a ratio of 2 to 1, that means;
-------------- [equation 1]
- The second condition states that when 4 years have passed, the ratio of their ages will be 8 to 6, that means;





= 2 years
Putting the value of y in equation 1 we get;
x = 2y
x =
= 4 years
Hence, the age of brothers are 4 years and 2 years respectively.
31.+ addition
32. - subtraction
Answer:
x = 9
Step-by-step explanation:
since the terms are in AP then there is a common difference between consecutive terms, that is
a₂ - a₁ = a₃ - a₂ ( substitute values )
x - 7 = 11 - x ( add x to both sides )
2x - 7 = 11 ( add 7 to both sides )
2x = 18 ( divide both sides by 2 )
x = 9
Answer:
A) 1/3200000
B) 19/20
Step-by-step explanation:
Percentage population of graduates = 5
Proportion of graduates from 100 random samples = percentage × number of samples
Proportion of graduates = 0.05 × 100 = 5
Probability of having 5 graduates among the 100 random samples:
P(1 graduate) = possible outcome / total required outcome
P(1 graduate) = (5 / 100) = 1/20
P(5 graduates) = (1/20)^5
P(5 graduates) = 1/3200000
Probability of never being a graduate = (1 - probability of being a graduate)
Probability of never being a graduate = ( 1 - (1/20)) = 19/20