Unit 6 · Algebra

1000 − 530 − 140 — Farm Costs How Many Points?

Lesson 4 of 12

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About this lesson

A player starts with 1000 game points, buys 5 buildings at 106 each and 1 farm, and has 140 left. What did the farm cost? This is a classic working-backwards equation: start − buildings − farm = leftover. The trap is option C (470) — students who calculate 1000 − 530 = 470 correctly but forget to subtract the 140 points remaining.

Chapters

0:00Introduction
0:23The Question
1:04Calculating the Cost of the Buildings
1:33Bar Model — Total Points Split
2:00Calculating the Farm's Cost
2:30Selecting the Correct Option
2:47Correct answer

Question

I am playing a computer game and I have 1000 points.

In the game, I buy 5 buildings, each costing 106 points. I also buy 1 farm.

I have 140 points left afterwards.

How many points did the farm cost?

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