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Algebra — substitute
Find 4x + 4 when x = 6.
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The pattern behind it: Algebra basics
Use a letter for an unknown number and work with what it means.
In this one. Replace every x with its given value, then multiply before adding.
How to spot it
A story with a repeated cost and a fixed fee, written as an expression like 4x + 4, points here. So does a value for x to substitute in.
Common mistake
Children swap the two numbers round, using the fixed fee as the price per ticket and the price per ticket as the fixed fee.
Try one like it
Standard Algebra — interpret Tickets cost $6 each, with a booking fee of $5. The total cost in dollars is 6x + 5. What does x represent?The 33 problem patterns
All 33 patterns, one to a page — the 19 behind Primary 5 and 6 word problems, and the skills the younger years are built on. The bar model, how to spot it in the question, and the mistake children make. A booklet you can print. Free.
A PDF, and a note when new solutions go up.