Grade 4 - Progress in Mathematics

Equations

14-1

A scout troop is planning a trip to a cave.

They rent a minibus for $17 per hour.

The trip will take 5 hours. How much

will the bus cost?

Write an equation, or a number sentence,

to help you solve the problem.

Use a variable to stand for the unknown.


Let nstand for how much the bus will cost.


Write the equation. 5 
$1 7 n


Solve for n. $85 n

The bus will cost $ 85.

Choose the correct equation for each problem.

Then solve each problem.

1. The first cave chamber was 18 feet high.
   The second chamber was only 4 feet high.
   How much higher was the first chamber?


2. The scouts discovered 225 bats in the first
   chamber and 172 in the second. How many
   bats did they discover in the two chambers?

What do you know?

What do you need Which operation

to know? will you use?


bus costs $17 
how much the 
multiplication

per hour bus will cost


trip takes 5 hours for 5 hours

a. 4  18 n

b. 4 
 18 n

c. 18  4 n

a. 225  172 n

b. 225  172 n

c. 172 
 225 n

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