There are five numbers. The second number is 25% more than the first or third number, the fourth number is 5/4 of the third number and the fifth number is 3/2 of the third number. What is the average of the five numbers if the first number is 40?
- A50
- B45
- C48
- D40
Solution & Step-by-step Explanation
Let the five numbers be N
1
,N
2
,N
3
,N
4
, and N
5
.
Given, First number (N
1
) = 40.
Second number (N
2
) is 25% more than the first number:
N
2
=40+25% of 40=40+10=50
N
2
is also 25% more than the third number (N
3
):
N
2
=1.25×N
3
⟹50=
4
5
×N
3
⟹N
3
=40
Fourth number (N
4
) is
4
5
of the third number:
N
4
=
4
5
×40=50
Fifth number (N
5
) is
2
3
of the third number:
N
5
=
2
3
×40=60
Now, find the average of the five numbers:
Sum=N
1
+N
2
+N
3
+N
4
+N
5
=40+50+40+50+60=240
Average=
5
Sum
=
5
240
=48
1
,N
2
,N
3
,N
4
, and N
5
.
Given, First number (N
1
) = 40.
Second number (N
2
) is 25% more than the first number:
N
2
=40+25% of 40=40+10=50
N
2
is also 25% more than the third number (N
3
):
N
2
=1.25×N
3
⟹50=
4
5
×N
3
⟹N
3
=40
Fourth number (N
4
) is
4
5
of the third number:
N
4
=
4
5
×40=50
Fifth number (N
5
) is
2
3
of the third number:
N
5
=
2
3
×40=60
Now, find the average of the five numbers:
Sum=N
1
+N
2
+N
3
+N
4
+N
5
=40+50+40+50+60=240
Average=
5
Sum
=
5
240
=48