Your grandfather's salary was $10,000 in 1967 and it was $40,000 in 1997. Assume the price index for 1967 was 100 and the price index for 1997 was 420. Calculate the real income for your grandfather in 1997.
Select one:
a. $9,524
b. $9,375
c. $40,000
d. $42,000