Amy and Ada both need to travel x km to go to school.
One morning, they set off at the sametime.
Amy walked at 5 km / h for 12 minutes,
and then got on a bus which travelled at 20km/h
for the rest of the journey.
Ada travelled the whole journey in a car at 30 km/h and arrived at
school 45 minutes before Amy.
(a) Find, in terms of x, the time taken by Amy and
that taken by Ada to get to school. (3 marks)
(b) Hence, find the value of x .