Unit 6 · Algebra

8 Then 3 Points — Fewest Coins for 120?

Lesson 10 of 24

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About this lesson

Kira earns 8 points for the first coin and 3 points per coin after that. She needs at least 120. Write the total as an expression in n (number of coins), set it ≥ 120, and solve — rounding UP since you can't collect a fraction of a coin.

Chapters

0:00Introduction
0:24The Question
0:58Isolating the initial milestone
1:27Setting up the inequation
1:52Handling the remainder with ceiling division
2:25Summing the complete coin inventory
2:50Exam strategy — the boundary rounding trap
3:34Confirming the final option

Question

In a video game, players collect coins.

Kira scores 8 points for the first coin she collects.

Then she scores 3 points for each coin she collects after that.

She wants to score at least 120 points altogether.

What is the smallest number of coins Kira must collect?

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