Lesson 1.17: Percent – Discount, VAT, Savings, Salaries & Interest | SEA Mathematics | My Carib Academy
SEA 2025-2028 Framework Aligned

💰 Lesson 1.17: Percent – Discount, VAT, Savings, Salaries & Interest

Master discount, VAT, savings, salaries, wages, interest, proportions and sharing. This lesson covers SEA Mathematics Objectives 96-99 from the Number Strand.

75 Minutes
Module 1: Number
Objectives 96-99
2 Videos
Lesson Progress 0%

Previous Lesson

Did you complete Lesson 1.16? Review Percent Ordering & Word Problems →

Learning Objectives

By the end of this lesson, you will be able to:

  • Calculate discount and sale prices (Objective 96)
  • Calculate VAT (Value Added Tax) on purchases (Objective 96)
  • Calculate savings from discounts (Objective 96)
  • Calculate salaries and wages (Objective 97)
  • Calculate simple interest (Objectives 98-99)
  • Solve proportion and sharing problems (Objectives 97-99)

SEA Tip

Money and percent word problems appear in Section II and III of the SEA Math paper. These are practical life skills for shopping and banking! (SEA Framework Page 21-22)

Watch: VAT (Value Added Tax)

Start by watching this video to learn how to calculate VAT on purchases. Take notes as you watch! 📝

VAT (Value Added Tax) – Mathematics Video Lesson

Quick Check

Did you understand the video? Review the notes below before continuing! ✅

VAT & Discount

VAT (Value Added Tax) is a tax added to the price of goods and services. In Trinidad & Tobago, VAT is typically 12.5%.

Key Formulas

  • VAT Amount: Price × VAT Rate (as decimal)
  • Total with VAT: Price + VAT Amount
  • Discount Amount: Original Price × Discount Rate
  • Sale Price: Original Price − Discount Amount
  • Savings: Same as Discount Amount

📊 Example 1: Calculating VAT

Finding VAT on a Purchase

Question: A laptop costs $5,000. VAT is 12.5%. What is the total cost?

Solution:

  1. Find VAT amount: $5,000 × 0.125 = $625
  2. Add to price: $5,000 + $625 = $5,625

Answer: $5,625 total cost

📊 Example 2: Calculating Discount

Finding Sale Price

Question: A shirt costs $200. It is on sale for 25% off. What is the sale price?

Solution:

  1. Find discount: $200 × 0.25 = $50
  2. Subtract from original: $200 − $50 = $150

Answer: $150 sale price

📊 Example 3: Calculating Savings

Finding How Much You Save

Question: A TV costs $8,000. It is on sale for 20% off. How much do you save?

Solution:

  1. Find discount (savings): $8,000 × 0.20 = $1,600

Answer: $1,600 savings

Watch: Discount & Sales

Now watch this video to learn more about discount and sale price calculations. Pay attention to the steps! 🎯

Discount and Sales – Mathematics Video Lesson

Salaries, Wages & Interest

Understanding how salaries, wages and interest work is essential for managing money in real life!

📋 Key Terms:

Definitions
Term Definition
Salary Fixed amount paid monthly or yearly
Wages Amount paid per hour or per day
Interest Money earned on savings or paid on loans
Principal Original amount of money
Rate Percent per year (per annum)
Time Number of years

📊 Example 4: Calculating Wages

Hourly Wages

Question: John earns $50 per hour. He works 8 hours a day for 5 days. How much does he earn?

Solution:

  1. Hours per week: 8 × 5 = 40 hours
  2. Total wages: 40 × $50 = $2,000

Answer: $2,000

📊 Example 5: Simple Interest Formula

Simple Interest Formula

I = P × R × T

  • I = Interest earned or paid
  • P = Principal (original amount)
  • R = Rate (as decimal, per year)
  • T = Time (in years)

📊 Example 6: Calculating Simple Interest

Finding Interest Earned

Question: Mary saves $10,000 at 5% simple interest per year. How much interest will she earn in 3 years?

Solution:

  1. Use formula: I = P × R × T
  2. Substitute: I = $10,000 × 0.05 × 3
  3. Calculate: I = $1,500

Answer: $1,500 interest

📊 Example 7: Sharing in Proportions

Sharing Money in a Ratio

Question: $500 is shared between Ann and Bob in the ratio 2:3. How much does each get?

Solution:

  1. Total parts: 2 + 3 = 5 parts
  2. Value of one part: $500 ÷ 5 = $100
  3. Ann’s share: 2 × $100 = $200
  4. Bob’s share: 3 × $100 = $300
  5. Check: $200 + $300 = $500 ✓

Answer: Ann gets $200, Bob gets $300

Memory Trick

Simple Interest: I = PRT (Think: “I Prefer Real Tea”)
Sharing: Add the ratio parts, divide total, multiply each share

Quick Quiz

Test your understanding! Select an answer for each question. 💰

6 Questions
12 Minutes
70% to Pass

1. A $1,000 item has 12.5% VAT. What is the VAT amount?

2. A $200 shirt has 25% discount. What is the sale price?

3. John earns $50/hour and works 40 hours. How much does he earn?

4. $10,000 at 5% simple interest for 3 years. How much interest?

5. $500 shared in ratio 2:3. How much is the larger share?

6. What does VAT stand for?

0/6

Lesson Complete!

Great job finishing Lesson 1.17! You’re mastering real-life percent calculations for the SEA exam! 🎉

Back to SEA Maths

Learn More