Mathematics Standard • Year 11 • Module 3 • Lesson 4
Pay Slips — Reading and Calculating
Apply pay-slip reading skills to realistic payslips — decompose, verify, identify errors, conclude.
Problem 1 — Build a full fortnightly pay slip
Devi is a registered nurse. Her fortnightly pay record contains:
Ordinary pay: 76 hours at $36.40/hr
Overtime: 5 hours at time-and-a-half
First-aid allowance: $14.50 per week (over 2 weeks)
PAYG tax withheld: $782.00
Salary sacrifice super: $148.00
Set up: What are we solving for?
(i) Calculate Devi's gross fortnightly pay. 3 marks
(ii) Calculate the total deductions. 1 mark
(iii) Calculate Devi's net fortnightly pay. 1 mark
Stuck? Build the pay slip as a list: each line for one component, then total.Problem 2 — Spot the pay slip error
An accounts officer has produced a draft pay slip for one of her staff. She wants you to verify it.
Ordinary pay (38 hrs × $29.00): $1,102.00
Overtime (5 hrs at time-and-a-half): $145.00
Tool allowance (5 days × $17.50): $87.50
Gross pay shown: $1,334.50
Set up: What are we solving for?
(i) Recalculate the overtime line independently. 2 marks
(ii) State which line is wrong and what the recorded value should have been. 1 mark
(iii) Calculate the correct gross pay. By how much was the worker underpaid or overpaid? 2 marks
Stuck? OT rate = base × 1.5, then multiply by 5 — check against $145.00.Problem 3 — Reverse-engineer the gross
An apprentice mechanic looked at his bank account and saw a net pay deposit of $1,584.00 for a fortnight. He also knows from the ATO portal that his PAYG tax for that fortnight was $478.00, and his salary sacrifice super (set up by his employer) was $120.00.
Set up: What are we solving for?
(i) Calculate the total deductions. 1 mark
(ii) Calculate his gross fortnightly pay. 2 marks
(iii) Convert the gross fortnightly pay to an annual figure. 1 mark
Stuck? Gross = Net + Deductions. Then × 26 for annual.Problem 4 — Verify the net pay on a payslip
A small-business owner has produced a payslip for a casual chef.
Ordinary pay (32 hrs × $28.50): $912.00
Saturday penalty (5 hrs at time-and-a-half): $213.75
Uniform allowance: $24.00
PAYG tax: $268.00
Net pay shown: $876.75
Set up: What are we solving for?
(i) Calculate the gross pay (the sum of the three earning lines). 1 mark
(ii) Calculate the correct net pay (gross − tax). 2 marks
(iii) The payslip shows $876.75 net. Is this correct? If not, state by how much and in which direction. 2 marks
Stuck? Recompute, compare, decide.Problem 5 — YTD column trap
A payslip shows two columns: This Pay and YTD.
This Pay YTD
Ordinary pay $1,520.00 $39,520.00
Overtime $114.00 $972.00
Allowance $36.00 $936.00
PAYG tax $392.00 $10,108.00
Set up: What are we solving for?
(i) Using the This Pay column only, calculate gross pay and net pay for the current week. 2 marks
(ii) A student calculated net pay as $39,520 + $972 + $936 − $10,108 = $31,320 using the YTD column. State in one sentence why this is wrong (what does $31,320 actually represent?). 2 marks
(iii) Approximately how many weeks of pay are represented by the YTD ordinary-pay column? 1 mark
Stuck? Divide YTD ordinary by This Pay ordinary.How did this worksheet feel?
What I'll revisit before next class:
Problem 1 — Devi's fortnightly pay slip
Set up. Build the pay slip line by line, sum for gross, sum deductions, subtract for net.
(i) Ordinary = $36.40 × 76 = $2,766.40.
OT rate = $36.40 × 1.5 = $54.60/hr → OT pay = $54.60 × 5 = $273.00.
Allowance = $14.50 × 2 = $29.00.
Gross = $2,766.40 + $273.00 + $29.00 = $3,068.40.
(ii) Total deductions = $782.00 + $148.00 = $930.00.
(iii) Net = $3,068.40 − $930.00 = $2,138.40.
Problem 2 — Spot the error
Set up. Recalculate the overtime line and compare.
(i) OT rate = $29.00 × 1.5 = $43.50/hr. OT pay = $43.50 × 5 = $217.50.
(ii) The overtime line is wrong. It shows $145.00 (= $29 × 5, no multiplier). It should be $217.50.
(iii) Correct gross = $1,102.00 + $217.50 + $87.50 = $1,407.00. The pay slip showed $1,334.50, so the worker was underpaid by $72.50.
Problem 3 — Back-calc to gross then annual
Set up. Net + Deductions = Gross, then × 26.
(i) Total deductions = $478.00 + $120.00 = $598.00.
(ii) Gross fortnightly = $1,584.00 + $598.00 = $2,182.00.
(iii) Annual = $2,182.00 × 26 = $56,732.00 per year.
Problem 4 — Verify casual chef payslip
Set up. Recompute gross, subtract tax, compare with shown net.
(i) Gross = $912.00 + $213.75 + $24.00 = $1,149.75.
(ii) Correct net = $1,149.75 − $268.00 = $881.75.
(iii) The payslip shows $876.75. Correct = $881.75. The payslip is $5.00 too low — the chef has been underpaid by $5.00 this pay.
Problem 5 — YTD trap
Set up. Use only the This Pay column. YTD is the running total since 1 July.
(i) Gross (this pay) = $1,520.00 + $114.00 + $36.00 = $1,670.00. Net = $1,670.00 − $392.00 = $1,278.00.
(ii) $31,320 is the YTD net pay (the cumulative net pay since the start of the financial year), not the net pay for the current week. The YTD column tracks running totals — it should not be treated as a single-period figure.
(iii) Weeks worked = $39,520 ÷ $1,520 = 26 weeks (a half-year mark — half of 52).