To explain a wage difference, sort the supplied facts into what affects demand for the worker and what affects the supply of workers, then say how each pushes the wage up or down. This appears in short explain questions and in data-response items about two occupations.
It is the first skill in labour and wages, and every later lesson builds on it.
How do you build the explanation?
Treat the wage as a price. Employers demand labour because the worker helps produce something they can sell. Workers supply labour depending on how many are qualified and willing to do the job at a given pay.
Use these steps:
- List the supplied facts for both jobs.
- Tag each fact as demand side (value of output, number of vacancies) or supply side (training time, number of qualified workers).
- Say the direction: high value of output and few qualified workers push a wage up.
- Link to the wage gap with a figure from the data.
Worked example
In the fictional town of Tanjung Lerai, the data supplied is:
| Factor | Crane operator | Café assistant |
|---|---|---|
| Monthly wage | RM 4,800 | RM 2,000 |
| Training needed | 18 months, licensed | 2 days, on the job |
| Qualified workers in town | 40 | 900 |
| Vacancies | 25 | 60 |
| Value of output per worker hour (supplied) | RM 120 | RM 28 |
Step 1, gap: 4,800 − 2,000 = RM 2,800, which is 2,800 ÷ 2,000 = 140% of the café wage. Equivalently, 4,800 ÷ 2,000 = 2.4 times.
Step 2, supply side: only 40 people hold the licence against 900 who can start as café assistants. Training takes 18 months, so the supply of operators cannot quickly rise.
Step 3, demand side: the value of output per worker hour is RM 120 against RM 28, so employers gain more from each operator hour.
Step 4, tie together: vacancies are 25 against 40 qualified workers, so port firms are competing for 62.5% of everyone qualified (25 ÷ 40). Café owners need 60 of 900, only about 6.7%. Strong demand meeting scarce supply gives a high wage.
The mistake to watch for
Mistaken answer: “The crane operator earns more because the job is more important and more dangerous.”
Importance and danger are opinions or unsupplied claims here, and the data never says danger affects pay, and “important” could describe a café just as easily. The answer also names no side of the market. The correction is to cite the supplied facts: scarce licensed workers (supply) and higher value of output per hour (demand).
Check yourself
1. A sea pilot earns RM 7,200 a month and a ferry ticket clerk earns RM 2,400. Training for a pilot takes 3 years and 12 people are qualified, with 10 vacancies. A clerk needs 1 week of training, 300 people can do the job and there are 20 vacancies. Explain the gap in two or three sentences.
Show answer
The pilot wage is 7,200 ÷ 2,400 = 3 times the clerk wage. On the supply side, only 12 people qualify and training takes 3 years, against 300 for clerks. On the demand side, 10 vacancies for 12 qualified people shows strong competition for pilots, while 20 vacancies among 300 is weak competition. Scarce supply and strong demand explain the higher wage.
2. Label each as demand side or supply side: (a) training takes 3 years; (b) each pilot hour saves shipping firms RM 900.
Show answer
(a) supply side, because it limits how many people can become pilots. (b) demand side, because it raises what employers will pay for the worker’s output.
3. In the crane example, the café wage is RM 2,000 and the operator wage is RM 4,800. What percentage of the operator wage is the gap?
Show answer
2,800 ÷ 4,800 = 0.5833, so the gap is about 58.3% of the operator wage. Note the base: this is not the 140% figure, which uses the café wage as the base.
Where this leads next
The next step is to separate the two sides carefully in distinguish demand for labour from worker supply. When you are ready, try the labour and wages practice set. The percentage-base explorer helps with the gap calculations, and the ratios tool shows what a ratio can and cannot tell you.
Some students know the factors but blur them in writing. That is the kind of pattern a teacher can spot quickly in online one-to-one Economics tuition.