please anyone can solve this tomorrow is my maths exam
Answers
CI f xi fixi
0 - 20 5 10 50
20 - 40 8 30 240
40 - 60 x 50 50x
60 - 80 12 70 840
80 - 100 7 90 630
100 - 120 8 110 880
--------- ----------
∑fi = 40 + x ∑fixi = 2640 + 50x
Now,
Given Mean = 62.8.
= > Mean = ∑fixi/∑fi
= > 62.8 = (2640 + 50x)/40 + x
= > 62.8(40 + x) = (2640 + 50x)
= > 2512 + 62.8x = 2640 + 50x
= > -128 = -12.8x
= > -128/12.8 = x
= > x = 10.
Therefore, the value of x = 10.
Hope it helps!