Dhanu has a model railway.
(a) He has a train that consists of a locomotive and 4 coaches.
The mass of the locomotive is 87g and the mass of each coach is 52g.
(i) Work out the total mass of the train.
(ii) Work out the mass of the locomotive as a percentage of the total mass of the train.
(b) The train is 61cm long and travels at a speed of 18cm/s.
It takes 4 seconds for the whole of the train to cross a bridge.
Calculate the length of the bridge.
(c) A new locomotive costs \($64\).
Calculate the cost of the locomotive in rupees when the exchange rate is 1 rupee = \($0.0154\).
Give your answer correct to the nearest 10 rupees.
(d) The cost of a railway magazine increases by 12.5% to \($2.70\).
Calculate the cost of the magazine before this increase.
(e) Dhanu plays with his model railway from 0650 to 11 15.
He then rides his bicycle for 3 hours.
Find the ratio time playing with model railway : time riding bicycle.
Give your answer in its simplest form.
(f) The value of Dhanu’s model railway is \($550\).
This value increases exponentially at a rate of r% per year.
At the end of 5 years the value will be \($736\).
Calculate the value of r.
