Class 4 Maths Chapter 6: Measuring Length NCERT Solutions

1. Let Us Observe

1. Look at the picture. What are the students measuring? Put a tick mark (✓) if you find it being measured.

• a) Length
• b) Height
• c) Weight
• d) Depth
• e) Breadth
• f) Temperature

Answer: The students are measuring length/height/breadth (all are measures of length). Weight, depth and temperature are not shown in the description, so they are not being measured.

2. What is being used to measure the height? What other tools can be used to measure height?

Answer: A measuring tape (or metre scale) is being used to measure the height. Other tools that can be used are a metre ruler, a measuring rod, a tailor’s tape, or a wall-mounted height scale.

3. Recall in Grade 3 you studied that lengths are measured in metres. Check and fill in the blanks whether the following are correct/incorrect for your classroom:

• a) The height of most of the students in my grade is more than a metre. _______________
• b) The length of my arm is less than a metre. _______________
• c) The height of the door of the grade is less than a metre. __________
• d) The breadth of the blackboard is more than a metre.___________

Answer: a) Correct b) Correct c) Incorrect (the classroom door is usually more than 1 m high) d) Correct (most blackboards are broader than 1 m).

2. Measuring is Fun

1. Walk, Jump, and Crawl on 1, 5 and 10 m line

Answer: Draw straight lines of 1 m, 5 m and 10 m on the ground using a metre rope or metre scale repeatedly. Then walk, jump and crawl along each line to experience and compare the different lengths.

2. Recalling Ropes of Length

Answer: 1 m = 1/2 m + 1/2 m 1 m = 1/4 m + 1/4 m + 1/4 m + 1/4 m 1/2 m = 1/4 m + 1/4 m These equalities show how one metre can be divided into halves and quarters.

3. Long Jump

Answer: Each child estimates whether their jump will be less than 1 m, about 1 m or more than 1 m, and then measures the actual length using a metre tape. The child with the maximum measured distance jumped the longest, and the one with the minimum distance jumped the shortest.

4. Estimate Your Classroom

Answer: First, guess the length and breadth of your classroom in metres. Then measure both using a metre tape or metre rope. Compare your answers with your friends to see whose estimate is closest to the actual measurements.

3. Let Us Think: Guess the Length

1. What is the length of one bus in metres? What is the length of a cricket bat?

Answer: A bus is usually about 8–10 metres long. A cricket bat is usually about 0.8–1 metre long. (Exact answers may vary slightly depending on the actual bus and bat.)

2. How many buses equal two blue whales in length?

Answer: If one blue whale is about 25 m long, two whales are about 50 m. If one bus is taken as about 10 m, then approximately 5 buses will equal two blue whales in length.

3. How many cricket bats will equal the length of one whale?

Answer: If one whale is about 25 m long and one cricket bat is about 1 m long, then about 25 cricket bats placed one after another will equal the length of one whale.

4. If two ostriches stand one above another, their height is equal to:

Answer: If one ostrich is about 2 m tall, then two ostriches one above the other will be about 4 m tall. This can be compared with another object of similar height given in the textbook picture.

5. How many crocodiles equal the length of one blue whale?

Answer: If one crocodile is about 3 m long and one blue whale is about 30 m long, then about 10 crocodiles will equal the length of one blue whale.

4. Centimetres and Metres

1. Observe the measuring tape. Each red bar is 1 cm. 10 cm = 10 red bars. 1 metre = 100 cm.

• ½ m = _____ cm
• ¼ m = _____ cm

Answer: ½ m = 50 cm ¼ m = 25 cm.

Measuring Small Things

1. Measure each object using a scale. Write the names in increasing order of length.

Answer: Measure all given objects with a centimetre scale. Then list them starting from the shortest to the longest. A possible order (short to long) could be: ant, grain of wheat, rajma seed, fingernail, eraser. Actual order may vary slightly with real measurements.

2. Estimate and Compare Objects

Answer: First, guess whether each item is equal to 1 cm, more than 1 cm or less than 1 cm, and tick the correct column. Then measure each object with a scale and write its actual length in centimetres in the last column.

3. Measure Toy Car Distances

Answer: Use a ruler or measuring tape to measure how far each toy car moves in centimetres. Write these distances in the table and rank the cars: rank 1 for the car that moved the farthest, rank 2 for the next, and so on.

4. Map Treasure Hunt

Answer: Measure each possible route using the 1 cm tiles on the map. Add the lengths of the yellow tiles for each route. The route with the least total length is the shortest, and the one with the greatest total length is the longest.

5. Use Your Hand for Estimating

Answer: First, trace your hand on paper and measure its length using a scale. Then, use your hand as a non-standard unit to estimate the length or height of objects like a textbook or chair. Finally, check each estimate with a scale and record both estimated and actual lengths.

6. Number Line

Answer: Mark and fill the points on the number line between 0 m and 2 m at equal intervals. For example, you will write 0 m, 0.5 m, 1 m, 1.5 m and 2 m (or 0 cm, 50 cm, 100 cm, 150 cm, 200 cm) depending on the number line shown.

7. Sticker Activity

Question: A board is 2 m long. Stickers are 20 cm each. How many are needed?

Answer: Length of board = 2 m = 200 cm Length of one sticker = 20 cm Number of stickers = 200 ÷ 20 = 10 So, 10 stickers are needed.

Question: Ramu's height is 120 cm. Shamu says 1 m 20 cm. Who is right?

Answer: Both are correct. 1 m = 100 cm, so 1 m 20 cm = 100 cm + 20 cm = 120 cm. Thus, 120 cm and 1 m 20 cm are the same height.

8. Conversions

• 1 m 40 cm = 140 cm
• 2 m 30 cm = 230 cm
• 4 m 60 cm = 460 cm
• 5 m 50 cm = 550 cm

Answer: Each metre is changed to 100 cm and then added to the centimetres: 1 m 40 cm = 100 + 40 = 140 cm 2 m 30 cm = 200 + 30 = 230 cm 4 m 60 cm = 400 + 60 = 460 cm 5 m 50 cm = 500 + 50 = 550 cm.

9. Well Depth Measurement

Convert m to cm:

• i) 2 m = 200 cm
• ii) _____ m = 400 cm
• iii) 6 m = _____ cm
• iv) _____ m = 800 cm

Answer: i) 2 m = 200 cm ii) 4 m = 400 cm iii) 6 m = 600 cm iv) 8 m = 800 cm.

5. Let Us Explore

Activity: Measure Your Height

Answer: Measure each child’s height in centimetres with a measuring tape and write it in the table. Then convert each height into metres and centimetres (for example, 132 cm = 1 m 32 cm) and fill the second column.

Fencing and Lacing

Answer: The length of the boundary of a shape is called its perimeter. To fence Bhola’s vegetable garden, we must find the perimeter of the garden and then arrange enough bricks or rope to cover that total boundary length.

Questions

1. Height of the tallest child: _____
2. Height of the shortest child: _____
3. No. of children over 1 m: _____
4. No. of children below 1 m: _____

Answer: Measure each child’s height using the table. The child with the maximum height is the tallest and the one with the minimum height is the shortest. Count how many heights are more than 1 m and how many are less than 1 m and fill in the blanks.

1. Circle the Longest Boundary

Answer: Look at the different shapes or paths given and compare their boundary lengths using a scale or counting units. Circle the shape which has the greatest total boundary length (perimeter).

2. Dot Grid Activity

Answer: On the dot grid, count the units around each shape to find its perimeter. Colour the shape with the longest perimeter in blue and the one with the shortest perimeter in green. Put a tick on shapes that have the same perimeter.

3. Match Same Perimeter Shapes

Answer: For each shape from A to F, count the length of all the sides using the given scale or grid, and calculate its perimeter. Then match and tick the pairs of shapes that have equal perimeters.

4. Minimum Perimeter Garden

Answer: Find the perimeter of each garden shape by adding the lengths of all sides. The garden which has the smallest total boundary length has the minimum perimeter and needs the least fencing. Select and mark that garden.

5. Estimate and Measure Perimeters

Answer: First, estimate the perimeter of each object (desk, blackboard, classroom floor, etc.) and write your guess. Then measure all sides with a tape or scale, add them to get the actual perimeter, and record the values in the table.

6. Draw Shapes with Perimeter 20 cm

Answer: Using grid or dot paper, draw any three different closed shapes so that the sum of the lengths of all their sides is 20 cm in each case. For example, a rectangle of 4 cm × 6 cm (perimeter 20 cm), or other shapes with different side lengths but the same total.

NCERT Solutions Class 4 Maths Chapter 6 Measuring Length (2025-26)

In Class 4 Maths Chapter 6, students explore **measuring length** using metres and centimetres. These NCERT Solutions for **Class 4 Maths Chapter 6 Measuring Length** (2025-26) explain each activity step by step so you can connect real-life examples like buses, whales and classrooms with numbers.

With clearly explained conversions between **metres and centimetres** and fun tasks on perimeter, these NCERT Class 4 Maths solutions make practice easy. Focus on reading scales correctly, counting centimetre blocks and estimating before measuring to build strong number sense for length-based questions.

While revising this chapter, regularly redo tables like long jump, toy car distance and garden fencing. Such **exercise-based practice** strengthens concepts of **length and perimeter**, helping you score full marks in measurement questions in your school exams.