What is a Two-Step Word Problem?

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Grade Level:

Class 4

Maths, NLP, AI, Logic

Definition

What is it?

A two-step word problem is a math problem that requires you to do two separate calculations (like addition, subtraction, multiplication, or division) to find the final answer. You can't solve it in just one go; you need to solve one part first, and then use that answer to solve the second part.

Simple Example

Quick Example

Imagine you bought 2 packets of biscuits for Rs. 10 each. Then you also bought a juice box for Rs. 25. To find out the total money you spent, you first need to multiply the cost of biscuits (2 x 10 = Rs. 20) and then add the cost of the juice box (20 + 25 = Rs. 45).

Worked Example

Step-by-Step

PROBLEM: Riya had 50 stickers. She gave 15 stickers to her friend, Pooja. Later, her mother gave her 20 more stickers. How many stickers does Riya have now?

STEP 1: Find out how many stickers Riya had after giving some to Pooja.
--- Riya started with 50 stickers.
--- She gave away 15 stickers.
--- Calculation: 50 - 15 = 35 stickers.

STEP 2: Find out the total number of stickers after her mother gave her more.
--- Riya had 35 stickers left.
--- Her mother gave her 20 more stickers.
--- Calculation: 35 + 20 = 55 stickers.

ANSWER: Riya has 55 stickers now.

Why It Matters

Solving two-step problems teaches you to break down big challenges into smaller, manageable parts, a skill crucial in fields like AI and Data Science. Engineers use this logic to design complex systems, and even game developers use it to program character actions. It builds your logical thinking, which is key for problem-solving in any career.

Common Mistakes

MISTAKE: Only performing one operation and stopping | CORRECTION: Always read the problem carefully to identify all the questions being asked and ensure you perform all necessary steps to reach the final answer.

MISTAKE: Using the wrong operation for a step (e.g., adding instead of subtracting) | CORRECTION: Pay close attention to keywords like 'gave away', 'total', 'left', 'each', 'combined' to determine the correct operation for each step.

MISTAKE: Not using the result of the first step in the second step | CORRECTION: The answer from your first calculation is usually the starting point for your second calculation. Make sure to carry it over correctly.

Practice Questions

Try It Yourself

QUESTION: A bus started with 45 passengers. At the first stop, 12 passengers got off and 8 passengers got on. How many passengers are on the bus now? | ANSWER: 41 passengers

QUESTION: Virat scored 68 runs in the first T20 match and 55 runs in the second match. If he needs to score a total of 200 runs across three matches to win a special award, how many runs does he need to score in the third match? | ANSWER: 77 runs

QUESTION: A shopkeeper bought 15 boxes of pens. Each box contains 20 pens. If he sold 180 pens, how many pens are left with him? | ANSWER: 120 pens

MCQ

Quick Quiz

Which of these is a two-step word problem?

What is the sum of 25 and 15?

If a shirt costs Rs. 350, how much do 3 shirts cost?

Rohan had Rs. 100. He bought a book for Rs. 40 and a pen for Rs. 20. How much money does he have left?

How many days are there in 5 weeks?

The Correct Answer Is:

Option C requires two steps: first, adding the cost of the book and pen (40 + 20 = 60), and then subtracting that total from Rohan's initial money (100 - 60 = 40). The other options can be solved in one step.

Real World Connection

In the Real World

When you plan a trip, like figuring out how much petrol you need for a 500 km journey if your car gives 10 km/litre and petrol costs Rs. 100/litre, you're solving a two-step problem. First, you calculate litres needed (500/10=50 litres), then the total cost (50x100=Rs. 5000). Even apps like Swiggy or Zomato use this to calculate your total bill, adding food costs and delivery charges.

Key Vocabulary

Key Terms

OPERATION: A mathematical action like addition, subtraction, multiplication, or division | KEYWORDS: Words in a problem that hint at which operation to use | STEP: A single calculation performed towards solving a problem | TOTAL: The final amount after adding or combining | LEFT: The remaining amount after subtracting or giving away

What's Next

What to Learn Next

Great job mastering two-step problems! Next, you can explore multi-step word problems, which involve three or more operations. This will further strengthen your problem-solving skills and prepare you for more complex mathematical challenges in higher grades.