The distace between the houses of Sarvesh and Ravi is 900 km and the houses of former is at 100 th milestone where as the house of Ravi's is at 1000th milestone. There are total 901 milestones at a regular interval of 1 km each. When you go to Ravi's house from the house of Sarvesh which are on the same highway, you will find that if the last digit (i.e., unit digit) of the 3 digit number on every milestone is same as the first (i.e., hundreds digit) of the number on the next mile stone is same, then these milestones must be red colour and rest will be of black.Total number of red colour milestone is :

Options

A. 179
B. 90
C. can't be determined
D. none of these

Answer

A