a minibus had 23 passengers at the beginning of a journey .12 passengers alighted at the first destination while 9 boarded.6 of those who boarded at the first stop alighted at the second stop as 12 got in. the minibus should not stop again to the final destination .the charges from the starting point to the first stop is sh 50 and sh70 up to the second stop. then sh.85 to the final destination .how much money was collected during the trip