What this lesson teaches
I can explain how a government manages trade-offs when it cannot give every group what it wants.
Syllabus K336, Issue 1, Guiding Question 3, Deciding what is good for society. Managing trade-offs
Make a guess
A town adds a bus lane on a busy road. What do you think it gains and gives up?
- Buses get faster, but cars have less of the road to use.
- Buses and cars both gain, because traffic is spread more evenly.
- Little changes, because drivers can still use the bus lane too.
Show the answer
Buses get faster, but cars have less of the road to use.
That is a trade-off. Limited road space means helping one group of road users takes something from another.
A trade-off means giving up some of one benefit to gain another, because not every aim can be fully met.
With limited money, space and time, not every aim can be met. A bus lane speeds up buses but leaves less road space for cars. That is a trade-off. In an answer, state both what is gained and what is given up.
Compare realistic options and their effects on different people. A change in design, timing or support may reduce a cost, but it may also create a new one. Explain why an option is justified in this situation, and what evidence might change your mind.
A trial gives evidence, not certainty. The mean journey time is the total time of all recorded journeys divided by the number of journeys. It can fall even if some journeys got slower. A before-and-after change may also be caused by different weather or traffic. So it does not prove, on its own, that the new design caused the improvement.
- Trade-off
- Giving up some of one benefit to gain another.
- Answer tip
- State the gain, the loss and why the choice is justified.
Real examples to use
Cross Island Line route, 2019
In December 2019 the government chose to run the Cross Island Line in deep tunnels under the Central Catchment Nature Reserve, instead of around it. The direct route meant shorter journeys and lower cost, while extra safeguards aimed to limit harm to the forest. Use it for a decision that gave up some of one aim to gain another.
Tengah HDB town
Tengah, a new HDB town in the west, gives homes to many families, but much of the forest on the site was cleared to build it. Use it to show that housing needs can come at a cost to green space.
Worked example: Later study hours
A study room could close at 10pm or at midnight. Later opening helps working adults who study at night, but neighbours complain about noise as people leave.
- Gain from midnight opening: more study time for working adults.
- Loss: less quiet for neighbours.
- A middle option, such as 11pm with a quiet exit route, reduces both the gain and the loss.
Watch out for this
A compromise removes every disadvantage.
A compromise usually reduces problems for everyone but rarely removes them all.
Check your understanding
Which statement describes a trade-off?
- Tengah's new HDB town was planned after the government asked residents for views.
- Tengah's new HDB town houses many families, but a forest was cleared for it.
- Tengah's new HDB town is popular with young couples buying their first homes there.
Show the answer
Tengah's new HDB town houses many families, but a forest was cleared for it.
Right. A benefit, new homes, was gained by giving up something else, the forest.
Check your understanding
The Cross Island Line was routed deep under the Central Catchment Nature Reserve. Which description fits the decision best?
- A win for both sides, because deep tunnels meant the forest above was left as it was.
- A trade-off: shorter, cheaper journeys against some risk to nature, reduced by building deep tunnels.
- A decision that put nature first, because the government chose the longer route around the reserve.
Show the answer
A trade-off: shorter, cheaper journeys against some risk to nature, reduced by building deep tunnels.
The choice gave up some things to gain others, and tried to reduce the harm.