Answer:
the probability that two 18 year old boys chosen at random will have heights greater than 185cm is 0.403
Step-by-step explanation:
P( x > 193) = 0.15
= 1- p(x less than or equal 193)
= 1 -p( z < (x- u) /sigma)
= 1- p( z< (193 - 187)/ sigma)
= 1- p( z< 6/ sigma)
P(z< 6/sigma) = 1 - 0.15
P(z < 6/sigma)= 0.85
6/sigma =1.036
Sigma= 6/1.036
Sigma= 5.79
P( x> 185) = 1- p( x< 185)
= 1- p (z < (185- 187)/5.79)
= 1- p( z< -0.345)
= 1- 0.365
= 0.635
P (x> 185) = 0.635 × 0.635
=0.403
Answer:
17
Step-by-step explanation:
Let us suppose two years ago my brother's age was x years
Then, my age was 3x
Three years from now, my brother's age will be (x +2+3) = (x+5) years
And my age will be (3x+2+3) = (3x+5) years
But it is given that i will be twice as old as my brother.
So, 2(x+5)= (3x+5)
or, x= 5 years
So my brother's present age is 5+2= 7 years
And my age is 5*3+2= 17 years
Answer: X + X= 2x or X squared.
Step-by-step explanation:
