Write an expression for 8 less than n.
n - 8
Start with n, then subtract the named amount.
Day 083Expressions for Costs
Standards 6.EE.A.2a6.EE.B.6
LEARNING TARGET
I can translate words and situations into expressions.
01 · LEARN
Build the idea
Define the variable first. Use parentheses for a sum or difference that must stay together. Read subtraction carefully: five less than n means n - 5, while five minus n means 5 - n.
A ticket costs $7. A group buys n tickets and pays a single $6 booking fee. Define n and write the total-cost expression. Evaluate it for n = 3.
n = ticket count; 7n + 6; $27
Ticket cost is 7 × n; add the one-time fee 6.
02 · PRACTICE
Your turn
Work in order. Start with the foundations, then build toward explanation and application.
Write an expression for 4 less than n.
Write an expression for 3 less than n.
Write an expression for 7 less than n.
Write an expression for 6 times the sum of x and 6.
Write an expression for 5 times the sum of x and 2.
Write an expression for 7 times the sum of x and 7.
A ticket costs $6. A group buys n tickets and pays a single $7 booking fee. Define n and write the total-cost expression. Evaluate it for n = 4.
A ticket costs $4. A group buys n tickets and pays a single $5 booking fee. Define n and write the total-cost expression. Evaluate it for n = 2.
A ticket costs $5. A group buys n tickets and pays a single $4 booking fee. Define n and write the total-cost expression. Evaluate it for n = 2.
A ticket costs $4. A group buys n tickets and pays a single $2 booking fee. Define n and write the total-cost expression. Evaluate it for n = 5.
03 · CHECK
Answers and reasoning
Reveal the teacher answer key
- n - 4
Start with n, then subtract the named amount.
- n - 3
Start with n, then subtract the named amount.
- n - 7
Start with n, then subtract the named amount.
- 6(x + 6)
Group the sum before multiplying.
- 5(x + 2)
Group the sum before multiplying.
- 7(x + 7)
Group the sum before multiplying.
- n = ticket count; 6n + 7; $31
Ticket cost is 6 × n; add the one-time fee 7.
- n = ticket count; 4n + 5; $13
Ticket cost is 4 × n; add the one-time fee 5.
- n = ticket count; 5n + 4; $14
Ticket cost is 5 × n; add the one-time fee 4.
- n = ticket count; 4n + 2; $22
Ticket cost is 4 × n; add the one-time fee 2.