Using the assumed - mean method, find the mean height of the plants from the following frequency-distribution table:
Height (in cm) xi6064687276Number of plants fi51640309
[4 MARKS]
Tabular form: 1 Mark
Concept: 1 Mark
Application: 2 Marks
Let the assumed mean be A = 68
Now, we may arrange the given data as under.
Height (in cm) xiFrequencydi=(xi−A) =(xi−68)fi×dixifi=(xi−68)605−8−406416−4−6468=A400072304120769872∑fi=100∑(fi×di)=88
Mean,
¯x=A +∑(fi×di)∑fi
=(68+88100)
=(68 + 0.88) = 68.88
Hence, mean height = 68.88 cm