Answer :
1 to 9=9
10 to 99= 90*2= 180
100-999= 900 *3 =2700
1000-1450 = 451*4 = 1804
9+180+2700+1804= 4693
= 4693 digits needed to number a 1450 page book
10 to 99= 90*2= 180
100-999= 900 *3 =2700
1000-1450 = 451*4 = 1804
9+180+2700+1804= 4693
= 4693 digits needed to number a 1450 page book