Consumer Mathematics: Insurance · Form 5
Consumer Mathematics: Insurance: Common Mistakes
The mistakes that quietly cost marks in Consumer Mathematics: Insurance, and how to avoid each one in the SPM exam.
In our experience teaching Consumer Mathematics: Insurance, most lost marks come from a small set of repeated slips, not from a lack of understanding. Here they are, with the fix for each.
Mistakes to avoid
- Using an outside insurance figure instead of the one in the question
- Misreading a coverage limit or excess
- Treating an example rate as a real, current one
Six more slips that quietly cost marks
- What students write: premium = RM5 × 70,000 = RM350,000. → Why it loses marks: the rate is per RM1,000 of cover, not per RM1. → Correct working: (70,000 ÷ 1,000) × 5 = 70 × 5 = RM350.
- What students write: NCD = 25% × 48,000 = RM12,000. → Why it loses marks: a No-Claim Discount reduces the premium, never the sum insured. → Correct working: on a RM1,400 premium, NCD = 25% × 1,400 = RM350, so payable = 1,400 − 350 = RM1,050.
- What students write: payout = (45,000 ÷ 60,000) × 45,000. → Why it loses marks: the average fraction multiplies the loss, not the sum insured. → Correct working: (45,000 ÷ 60,000) × 12,000 = 0.75 × 12,000 = RM9,000.
- What students write: payout = RM9,000, ignoring the RM500 excess. → Why it loses marks: the excess is the insured's own share and must be subtracted. → Correct working: 9,000 − 500 = RM8,500.
- What students write: 2.5% × 80,000 = 0.25 × 80,000 = RM20,000. → Why it loses marks: 2.5% is 0.025, not 0.25. → Correct working: 0.025 × 80,000 = RM2,000.
- What students write: with a 25% NCD, payable = 1,400 × 1.25 = RM1,750. → Why it loses marks: a discount is subtracted, so you multiply by (1 − 0.25). → Correct working: 1,400 × 0.75 = RM1,050.
The root cause behind most of these slips
Notice that almost every mistake above is a reading error, not a maths error: the wrong quantity is multiplied, a discount is added instead of subtracted, or a rate 'per RM1,000' is treated as 'per RM1'. The arithmetic in this chapter is easy; the marks are lost in translating the words into the right operation.
The fix is mechanical, label each number in the question with what it is (sum insured, value, loss, excess, rate), then decide the operation before touching the calculator. A number you cannot label is a signal you have misread the policy terms, so re-read that sentence rather than guessing.
Source:DSKP KSSM Mathematics Form 4 and 5 (Versi English)
Frequently asked questions
Is it a mistake to give the payout with no working if I got the number right?
In Paper 2 the marks are split between method and answer. A correct final figure with no substitution line can lose the method marks, and one small slip then costs everything.
Always show the average fraction and the excess subtraction on their own separate lines so the working can be credited.
I keep confusing which quantity the average fraction multiplies. Any fix?
The average fraction (sum insured ÷ value) always multiplies the loss, never the sum insured or the value. Read it as: 'the insurer pays the same fraction of your loss as you insured of the value.'
Insure only three-quarters of the value and you recover three-quarters of each loss.
Do I subtract the excess before or after the average clause?
Apply the average clause first to scale the loss down, then subtract the excess from that scaled figure. Doing it the other way understates the deduction.
So payout = (sum insured ÷ value) × loss, then minus the stated excess, and the result can never fall below zero.