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Lesson 19 — Mini project: cart total
Mini project: a shopping cart
A cart is an array of items, each with a price p and a quantity q. The line total is p * q; the cart total is the sum of all line totals. Many shops also give a discount above a threshold. toFixed(2) formats money with 2 decimals.
(57).toFixed(2) // "57.00"
Why it matters: this is real e-commerce logic — and a place where small bugs cost real money.
Compute the subtotal with reduce (p * q), then apply 10% off when the subtotal is 50 or more.
Run your code — when the output matches the task, you will see a green check. Then mark the lesson complete.
Test your knowledgeA quick 3-question quiz on this lesson — instant feedback.
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