The average earning of amechanic for the first 4days of a week is Rs.53 and for the last four days is Rs.22. If heearns Rs.20 on the fourth day, his average earning forthe whole week is?
Select the correct option:
A) s. 10 B) s. 20 C) s. 30 D) s. 40 E) s. 50
Total earning for the week = Sum of earning of first four days + Sum of earning of last four days - Earning of 4th day   = 4 x 53 + 4 x 22 -20   = Rs. 280   âˆ´ Average earning = 280/ 7   = Rs. 40   s. 40
<result>D</result>
The average earning of amechanic for the first 4days of a week is Rs.53 and for the last four days is Rs.22. If heearns Rs.20 on the fourth day, his average earning forthe whole week is?