The following table shows the number of children in each house of a society.
Number of Children Number of Houses
0 3
1 9
2 18
3 3
What is the average number of children per house?
- A1.89
- B2.14
- C1.39
- D1.64
Solution & Step-by-step Explanation
To find the average number of children per house, we use the weighted average formula:
Average=
∑f
i
∑(f
i
×x
i
)
Where x
i
is the number of children and f
i
is the number of houses.
Total number of children=(0×3)+(1×9)+(2×18)+(3×3)
Total number of children=0+9+36+9=54
Total number of houses=3+9+18+3=33
Now, calculate the average:
Average=
33
54
≈1.6363...
Rounding to two decimal places gives 1.64.
Average=
∑f
i
∑(f
i
×x
i
)
Where x
i
is the number of children and f
i
is the number of houses.
Total number of children=(0×3)+(1×9)+(2×18)+(3×3)
Total number of children=0+9+36+9=54
Total number of houses=3+9+18+3=33
Now, calculate the average:
Average=
33
54
≈1.6363...
Rounding to two decimal places gives 1.64.