Solution :-
Total number of pages in the book = 150
Total number of one digit numbers = From 1 to 9
= 1*9
9 digits
Total number of two digit numbers = From 10 to 99
= 2*90
= 180 digits
Total number of three digit numbers = From 100 to 150
= 3*51
= 153 digits
Total number of digits printed in the book containing 150 pages
= Total number of one digit numbers + Total number of two digit numbers +
Total number of two digit numbers
= 9 + 180 + 153
= 342 Digits
Hence, total 342 digits are printed in the book which has 150 pages.