Please submit your concern

Explanation:

The CPI in 1970 is 43. But it has to be taken as 105. Presently in 1983 and 1975, the CPI is 149 and 78 respectively. Hence, they should actually be taken as $\left(149\times \frac{105}{43}\right)$ = 363.83 and $\left(78\times \frac{105}{43}\right)$ = 190.46 respectively. Hence, their difference = (363.83 – 190.46) = 173.37 = 174 (Approximately).