Percentages & Discounts
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Lesson overview
Percent of a number, increases and decreases — a GED staple.
Go to lesson quiz →Exam guidance · GED Reasoning & Formula-Sheet Lens
Pacing
~2–2.5 minutes per item with an on-screen calculator and official formula sheet.
How GED marks this
Translating word scenarios, charts, and tables into equations rather than rote formula memorisation.
Watch out for
Answering the wrong target quantity (e.g., solving for x when the prompt asks for 2x + 5 or percentage change).
Lesson content
Overview — Percentages & Discounts
Percent of a number, increases and decreases — a GED staple. This lesson is at the beginner level — by the end, you'll be able to recognise this question type, apply a reliable method, and avoid the traps that cost marks.
Key Concept
GED percent questions test finding a percent of a number, calculating a percent increase or decrease, and applying discounts — all everyday calculations built around one formula: part = percent (as a decimal) × whole.
Why It's Tested This Way
The GED tests percentages because they're the math skill adults use most in daily life — sales tax, discounts, tips, and interest — reflecting the exam's focus on practical, real-world numeracy rather than abstract theory.
Method
Identify the 'whole' the percent applies to first (the original price, the full amount), convert the percent to a decimal by dividing by 100, then multiply — for a discount, subtract that result from the original; for an increase, add it.
Worked Example
A $60 jacket is discounted 25%. The discount amount is 60 × 0.25 = $15, so the sale price is 60 − 15 = $45.
Second Worked Example
A worker's $18/hour wage increases by 8%. The raise amount is 18 × 0.08 = $1.44, so the new wage is 18 + 1.44 = $19.44/hour.
Common Traps
The trap is applying the percent to the wrong 'whole' — such as calculating a raise's percentage based on the new wage instead of the original wage — always identify the original starting value before calculating a percent change.
Lesson Summary
Remember: (1) identify what is being asked, (2) apply the GED strategy, (3) check against the traps. Complete the 10-question quiz below to unlock the next lesson — you need at least 60% to pass.
Mastery Check · Lesson Quiz · pass 60%
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