Question

Find out weighted mean by weighting each price by the quantity consumed:

Items	Quantity consumed (in kg)	Price in Rupees (per kg)
Apple	12	30
Mango	10	50
Tomato	10	40
Orange	15	35
Grapes	12	45

Answer 1

Items	Quantity (W)	Price (X)	WX
Apple Mango Tomato Orange Grapes	12 10 10 15 12	30 50 40 35 45	360 500 400 525 540
	$\mathit{\Sigma }\mathit{W}$=59		ΣWX= 2325

Now, weighted mean can be calculating using the following formula.

$$\begin{gathered} {\overline{X}}_W=\frac{\Sigma WX}{\Sigma W} \\ or,{\overline{X}}_W=\frac{2325}{59} \\ \Rightarrow {\overline{X}}_W=39.40 \end{gathered}$$

Hence, the weighted mean of the above series is 39.40