hi, in the multiple regression practice problems if we need to take some of the independent variables as ln (natural logarithm) and in the problem itsel;f it is $100 million (PP 3. p340 of current 2021 curricullum) they take it as ln(100). In the next problem , however when it says C$900 million they take ln(900,000) - why is that?

Sloppiness, or stupidity.

you made me check errata, but it is not corrected there. so which one we shall use ?

For the slope coefficients, it makes no difference; youâ€™ll get the same slopes either way.

The only difference will be in the intercept term.

In short, do it whichever way you prefer.