If the mean of the following frequency distribution is 4.5, find the misssing frequency f.
Variable12345678910Frequency512f1379123114
VariableFrequencyProductxyxy155212243f3f41352573569547128483249119910440Total∑y=76+f∑xy=417+3f
Mean = ΣxyΣy
⇒4.5=417+3f76+f
⇒342+4.5f=417+3f
⇒4.5f−3f=417−342
⇒1.5f=75
⇒f=751.5=50