Using Variables in Word Problems
Aligned to 6.EE.B.6 — Common Core State Standards for Mathematics.
What this lesson teaches
When a real-world quantity can change or is unknown, name it with a variable and build an expression that captures the situation. The variable holds the place for any number that could fit.
Worked example
A shirt costs $t. Buying 3 shirts and a $5 hat costs 3t + 5. If a shirt costs $12, that is 3 × 12 + 5 = $41.
Practice questions
- Let p be a book's price. Write an expression for the cost of 4 books.
- A taxi charges $3 plus $2 per mile. Write an expression for a ride of m miles.
- You had s stickers and gave away 7. Write an expression for how many remain.
Watch the lesson
Every lesson comes with a video taught in English and Spanish — the same video the QR code in the printed workbook opens.
▶ Watch this lessonEn español
Usar Variables en Problemas Verbales
Cuando una cantidad del mundo real puede cambiar o es desconocida, nómbrala con una variable y arma una expresión que represente la situación. La variable guarda el lugar de cualquier número que encaje.
Ejemplo: Una camisa cuesta $t. Comprar 3 camisas y un gorro de $5 cuesta 3t + 5. Si una camisa cuesta $12, eso es 3 × 12 + 5 = $41.
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