Question

For a given frequency distribution mean =19.7 assumed mean =20 and n=50 then fidi =?

Answer 1

mean=A+d
19.7=20+d
d=20-19.7
d=0.3
but
d=£fidi/£fi
0.3=£fidi/50
50*0.3=£fidi
£fidi=15
ok