Step-by-step explanation:
it is 50 km in total.
30 km are already covered by the initial rental amount (4000).
what is left is 50-30 = 20 km.
for these 20 km he has to pay 200 for every 5 km.
how many 5 km units are in 20 km ?
well, 20/5 = 4
so, he needs to pay additionally 200×4 = 800php.
therefore, the total cost will be
4000 + 800 = 4800php