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Grade 5 Math · Level 6, Grade 6 Preview

Equations, Inequalities & Quantitative Relationships

How the lesson starts: Equations, Inequalities & Quantitative Relationships

1. Ruby's balance scale

   Ruby sells apples with a balance scale. On one side: a mystery basket and 5 apples. On the other side: 12 apples. The scale balances! How many apples hide in the basket?

2. Undo the adding

   x + 5 = 12. To get x alone, undo the + 5: take 5 from both sides. x = 12 − 5 = 7. Check: 7 + 5 = 12! Watch out: change BOTH sides, or the scale tips.

3. Undo the times

   3 baskets with the same number of apples balance 15 apples: 3x = 15. Divide both sides by 3. x = 5! Check: 3 × 5 = 15.