Answer:
b. using a sample of size 40
Step-by-step explanation:
edg 2020
Answer:
son = 10 , father = 40
Step-by-step explanation:
Let Five years ago the age of son be x years and age of father be 7x years
Present age of son =x+5
Present age of father =7x+5
5 years later their age will (x+10) and (7x+10)
∴7x+10=3(x+10)
7x−3x=20
4x=20
x=5
So, the present age of son=x+5=5+5=10years
and the present age of father=7x+5=35+5=40years
hope it helps you
Answer:
length of a rectangle is 5 more than twice the length. I believe
you mean the length of a rectangle is 5 more than twice the
width.
From the information given we can make two equations,
thus forming a system to solve. We know the perimeter
of a rectangle is 2(length + width) and area = length*width.
length of a rectangle is 5 more then twice the width:
L = 2w + 5
The perimeter is 130:
2(L+w) = 130
L+w = 65
Since we know L=2w+5 we can substitute that into 2nd equation
to solve for w
2w + 5 + w = 65
3w = 60
w = 20
L = 2w+5 = 45
The area is length*width = 20(45) = 900 square units
Answer: 90
Explanation: The pattern is add 3 then the next set is double. [9-6=3 then 18-9=9(or doubled)] and the pattern continues and because 45-42=3 the next number set would be 45 doubles which equals 90.
