Solving Multi-Step Decimal Word Problems
Solving multi-step decimal word problems teaches Grade 5 students to identify the correct sequence of operations in real-world situations involving decimals. For example, if Jasmine buys a book for $14.95 and a pen for $2.75 and pays with $20, she first adds ($14.95 + $2.75 = $17.70) then subtracts ($20.00 − $17.70 = $2.30 change). Another example: a runner who ran 5.5 km on Monday and 1.25 km farther on Tuesday ran 6.75 km on Tuesday and 12.25 km total. This Pengi Math (Grade 5) Chapter 3 skill emphasizes careful decimal placement in multi-operation problems.
Key Concepts
Property Solving multi step word problems involves identifying the necessary operations (addition, subtraction, multiplication, division) based on the context and performing them in the correct sequence to find the solution. There is no single formula; instead, you must build a plan from the information given.
Examples Jasmine buys a book for 14.95 dollars and a pen for 2.75 dollars. She pays with a 20 dollar bill. How much change does she get? First, find the total cost: $\$14.95 + \$2.75 = \$17.70$. Then, find the change: $\$20.00 \$17.70 = \$2.30$. A runner is training for a marathon. On Monday, they ran $5.5$ km. On Tuesday, they ran $1.25$ km farther than on Monday. How many kilometers did they run in total over the two days? First, find Tuesday''s distance: $5.5 + 1.25 = 6.75$ km. Then, find the total distance: $5.5 + 6.75 = 12.25$ km.
Explanation Real world problems often require more than one calculation to solve. To tackle these, first read the problem carefully to understand what is being asked. Next, identify the different pieces of information given and plan the steps needed to reach the final answer. Finally, perform the calculations in order, paying close attention to decimal placement, to solve the problem.
Common Questions
What is the general approach to multi-step decimal word problems?
Read carefully to understand the situation, identify all given information, plan the sequence of operations, then calculate step by step paying attention to decimal placement.
How do you solve: a book costs $14.95, a pen costs $2.75, and you pay with $20. What is the change?
First add the costs: $14.95 + $2.75 = $17.70. Then subtract from $20.00: $20.00 − $17.70 = $2.30 change.
How do you align decimals when adding or subtracting?
Write the numbers vertically with decimal points lined up in the same column. Add zeros as placeholders if needed so all numbers have the same number of decimal places.
A runner ran 5.5 km Monday and 1.25 km farther Tuesday. How far total?
Tuesday distance: 5.5 + 1.25 = 6.75 km. Total: 5.5 + 6.75 = 12.25 km over two days.
How do you know the order of steps in a multi-step problem?
Follow the sequence of events in the problem. What happens first in the story is usually calculated first. Look for clue words like 'then,' 'after,' or 'remaining.'
What grade and chapter covers multi-step decimal word problems?
Grade 5, Chapter 3: Decimal Operations and Estimation in Pengi Math.