Question 4
Suppose the length of a rectangular box is 7 cm and breadth is 11 cm. Find the volume if the height is (i) 5 cm, (ii) 9 cm, (iii) 13 cm. Find the linear pattern representing the volume of the rectangular box.
We will use the formula for the volume of a rectangular box.
Step 1 — Find the base area
Let's first find the base area. The length of the box is 7 cm. The breadth of the box is 11 cm. The formula for base area is length times breadth.

Step 2 — Calculate volumes for different heights
Now we can find the volume for each given height. The volume formula is base area times height.
(i) Height is 5 cm.
(ii) Height is 9 cm.
(iii) Height is 13 cm.

Step 3 — Determine the linear pattern
Let's find a general pattern for the volume. Let the height of the box be cm. We know the base area is 77 cm². The volume is base area multiplied by height.
Answer
(i) The volume is 385 cm³. (ii) The volume is 693 cm³. (iii) The volume is 1001 cm³. The linear pattern is V = 77h.
More questions in Exercise 2.3
Solve the following:
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A rally starts with 120 members. Each hour, 9 members drop out of the group. How many members will remain after 1, 2, 3, ... hours? Find a linear expression to represent the number of members at the end of the hour.
Suppose the length of a rectangle is 13 cm. Find the area if the breadth is (i) 12 cm, (ii) 10 cm, (iii) 8 cm. Find the linear pattern representing the area of the rectangle.
Suppose the length of a rectangular box is 7 cm and breadth is 11 cm. Find the volume if the height is (i) 5 cm, (ii) 9 cm, (iii) 13 cm. Find the linear pattern representing the volume of the rectangular box.
Sarita is reading a book of 500 pages. She reads 20 pages every day. How many pages will be left after 15 days? Express this as a linear pattern.