PSA_PRACTICE_QNR27. Todd agreed to work for his Dad for 20 days to get $ 500 and an iPod. He worked for only 10 days and had to quit for some reason. He got $ 200 and the iPod based on the amount of work done. How much was iPod valued?
Ans: Let the iPod cost be ‘c’.
Total agreed amount for 20 days= 500+c
For 10 days the amount= (1/2)*(500+c)= 250 + c/2
Also given, for 10 days, Todd gets= 200 + c
=> 200 + c = 250 + c/2
=> c/2= 50
It can also be calculated mentally: since todd did half of the job he should have got 500/2 and ‘half of iPod’ (or $250 and ‘half of iPod’). But he gets $200 which is more than $50. And since he got a ‘complete iPod’, definitely this excess $50 dollars compensated for the other ‘half of iPod’. Thus, an iPod will cost 2*50= $100.