Earning Money: Wages, Percentages and the Payslip

Two job ads: 'Cashier, ₱610/day' and 'Encoder, ₱15,860/month'. Which pays more? How do you know?

Learners write one thing they notice and one thing they wonder about the ads. Collect wonders on the board without answering them yet.

Groups receive one salary card each (annual, monthly, weekly, daily or hourly) and must express it in all other periods. They decide for themselves how many weeks and working days a year has, then compare answers across groups.

• "Why did your group get a different weekly amount from the next group?"
• "How many weeks are there in a year? How many working days?"

Consolidate: 12 months, 52 weeks, 8-hour day, and the standard conversions. Introduce overtime at 125% of the hourly rate for an ordinary day, allowances added to basic pay, commission as a percent of sales, and piecework as rate × pieces.

Each pair computes the weekly earnings of three workers and ranks them: a daily-wage worker with 6 hours of overtime, a sales agent on 4% commission of ₱95,000 sales plus ₱2,500 allowance, and a garment worker paid ₱18 per piece for 320 pieces.

A delivery rider earns ₱96 per hour for an 8-hour day and worked 2 hours of overtime at 125%. Compute the day's pay and explain each step in one sentence.

Accommodation: learners may use a calculator; provide the conversion table for learners who need it.

Find one job ad (print or online) and rewrite its pay as annual, monthly, weekly, daily and hourly amounts. State the assumptions you made.

A store cuts a ₱1,000 bag's price by 20%, then raises it by 20% a week later. Is it back to ₱1,000?

Learners vote (yes / no / not sure) and write one sentence of justification before any computation.

Groups receive real receipts (VAT-inclusive totals) and sale tags (percent off). They must recover the pre-VAT price and the original price before the discount, by any method, and record their method.

• "What number did you divide by, and why?"
• "Does 12% of the total give the VAT? Check it."

Introduce the single-multiplier form of a percent change and show that dividing by the multiplier reverses it.

Using the hook, show that ₱1,000 × 0.8 × 1.2 = ₱960. Then: if inflation was 6% last year and a worker's wage rose 4%, did the worker gain or lose purchasing power? Groups compute and present.

A sari-sari store buys a case of 24 cans for ₱480 and sells each at ₱25. Find the profit in pesos and as a percent of cost. Repeat for a case that spoils with only 15 cans sold.

Student A: 'The VAT on a ₱560 receipt is 12% of 560 = ₱67.20.' Student B: 'The VAT is 560 − 560 ÷ 1.12 = ₱60.' Decide, and prove it.

Accommodation: provide a partially completed table (old, multiplier, new) for learners who need structure.

Record the price of three goods your family buys (rice, eggs, cooking oil) today and ask an elder what they cost five years ago. Compute the percent increase of each. Which rose fastest?

A payslip (anonymised) shows a ₱25,000 salary but ₱22,717.45 received. Where did the money go, and is it gone?

Learners list every deduction they can read on the payslip and guess what each is for. Keep the list visible.

In pairs on one device (or on paper grids if no device), learners build a payslip: inputs (basic monthly pay, OT hours, hourly rate, allowances) at the top; then formulas for gross pay, each contribution (simplified rate or bracket lookup), taxable income, tax, and net pay. Teacher circulates and asks learners to change an input and watch the result.

Consolidate the sequence gross → contributions → taxable income → tax → net. Stress that contributions reduce taxable income, and that rates in the table are simplified teaching values that change yearly.

Pairs test: What if OT hours double? What if the allowance is removed? Which single input changes net pay most? Pairs record a one-line finding each.

Given gross pay ₱18,500 and the simplified rates, compute the three contributions, taxable income, tax and net pay by hand. Then state which spreadsheet cell you would change to model a ₱1,000 raise.

Accommodation: pre-built sheet with blanks for learners with no spreadsheet experience.

Write a four-sentence note to a new employee explaining why net pay is smaller than gross pay and what each deduction gives them in return.

You are the payroll clerk. A worker disputes her payslip. Can you prove every line?

Each group draws a worker profile card (e.g., a security guard with night-shift OT; a sales agent with commission; a teacher with allowances). Using Google Sheets they produce a payslip with formulas, then a one-paragraph explanation addressed to the worker.

• All computations must be formulas, not typed numbers.
• Show gross pay, each deduction, taxable income, tax and net pay.
• Round to centavos; state your assumptions.

Groups swap payslips. The auditing group checks each line against the rubric and raises at most three questions. Authors respond with evidence from the sheet.

One sentence each: 'The most surprising thing about pay is…'

The payslip and explanation are scored with the rubric. Peer audit questions are recorded as evidence of mathematical communication.

Using your group's net pay, draft a simple monthly budget (food, transport, utilities, savings) with percentages of net pay. Which category is largest?