class intervals- 0-100 100-200 200-300 300-400 400-500 500-600. frequency- 8 , 15 ,32 ,y-4 ,12 ,7. if the mean is 290 then find the value of y.
Answer:
And we know
Mean =
290 =
20300 + 290 y = 350 y + 18500
60 y = 1800
y = 30 ( Ans )
Class interval | Frequency ( f ) | Mid point ( x ) | f x |
0 - 100 | 8 | 50 | 400 |
100 - 200 | 15 | 150 | 2250 |
200 - 300 | 32 | 250 | 8000 |
300 - 400 | y - 4 | 350 | 350 y - 1400 |
400 - 500 | 12 | 450 | 5400 |
500 - 600 | 7 | 550 | 3850 |
( f ) = 70 + y | ( f x ) = 350y + 18500 |
And we know
Mean =
290 =
20300 + 290 y = 350 y + 18500
60 y = 1800
y = 30 ( Ans )