hi
1 mile is 1 609 meters. (rounded).
As there is 100 centimeters in a meter, then
1 mile is 160 900 centimeter.
Then 1.5 miles , is 1 mile + one half so :
160 900 + 160 900 /2 = 160 900 + 80 450
= 241 350
1.5 mile is 241 350 centimeters.
please note that the value of a mile was rounded.