A planning question gives you quantities and asks what to buy, prepare or spend. The arithmetic is the easy half; the harder half is turning the answer into something a household could actually do.
This lesson is part of the SPM subjects and learning resources section. Practical cooking and other school-assessed work stay with your school.
How do I read the quantities first?
Ask three questions before you calculate. What is being counted? What does one unit cover?
Ask also what must be left over, if anything. Writing the answers in the margin stops you from using a number that belongs to a different step.
Worked example: sandwiches for a class gathering
Here is an original task. A class of 24 students holds a gathering with a RM80 budget.
Each student eats 2 sandwiches. A loaf has 20 slices and costs RM3.80. One tin of tuna costs RM5.50 and fills 6 sandwiches. Each sandwich uses 2 slices.
Bread.
- Sandwiches needed: 24 × 2 = 48.
- One loaf makes 20 ÷ 2 = 10 sandwiches.
- Loaves needed: 48 ÷ 10 = 4.8. You cannot buy 0.8 of a loaf, and 4 loaves make only 40 sandwiches, so buy 5 loaves.
- Cost: 5 × RM3.80 = RM19.00.
Filling.
- Tins needed: 48 ÷ 6 = 8 exactly.
- Cost: 8 × RM5.50 = RM44.00.
Total and budget. RM19.00 + RM44.00 = RM63.00. The budget is RM80.00, so RM17.00 remains.
The plan fits the budget. Five loaves make 50 sandwiches, so enough bread for 2 sandwiches is spare.
The mistake that costs marks
The common slip is to stop at 4.8 and write “4.8 loaves”, or to round to 5 without saying why. Another is to use 24 students in the bread calculation and forget the 2 sandwiches each.
| Step | Slip | Correct |
|---|---|---|
| Sandwiches | 24 | 24 × 2 = 48 |
| Loaves | 4.8 loaves | 5 loaves, because 4 cannot cover 48 |
| Cost | 4.8 × RM3.80 | 5 × RM3.80 = RM19.00 |
Write the answer as a sentence
End with the quantity, the unit and the reason. For example: “The class should buy 5 loaves and 8 tins of tuna for RM63.00, which is within the RM80.00 budget.” A sentence like this shows the marker that you connected the number to the situation.
Check yourself
Thirty guests each drink 3 cups of syrup drink.
A cup holds 250 ml. One packet of syrup makes 5 litres. How many packets are needed, and why that number?
Answer
Each guest drinks 3 × 250 = 750 ml. For 30 guests: 30 × 750 = 22 500 ml, which is 22.5 litres.
Packets: 22.5 ÷ 5 = 4.5. Four packets make only 20 litres, which is short, so buy 5 packets.
Sentence: “Buy 5 packets, because 4 packets give only 20 litres and the guests need 22.5 litres.”
What to study next
Practise choosing between options with figures in justify a household resource decision with evidence. Then try the mixed questions in the Home Science original practice set.
The structured answer self-review helps you check that each answer has a figure, a unit and a reason. For help with your own questions, see online one-to-one Home Science tuition.