Surface Areas & Volumes | Exercise 13.1 | Q6

Question 6: A small indoor greenhouse (herbarium) is made entirely of glass panes (including base) held together with tape. It is 30 cm long, 25 cm wide and 25 cm high.
(i)  What is the area of the glass?
(ii) How much of tape is needed for all the 12 edges?

Video Explanation

Explanatory Answer | Exercise 13.1 Question 6

Dimensions of herbarium: length 30 cm, width 25 cm, and height 25 cm.

Part (i): Area of Glass

The herbarium is in the shape of cuboid.
Area of glass required to make the herbarium = Total surface area of cuboid (herbarium)
= 2 (lb + lh + bh)
= 2 (30 × 25 + 30 × 25 + 25 × 25)
= 2 (750 + 750 + 625) = 2 (2125)
= 4250 cm²

Part (ii): Length of Tape Required

The cube is having 12 edges.
Length of tape required = Length of 12 edges
= 4l + 4b + 4h = 4 (l + b + h)
= 4(30 + 25 + 25)
= 320 cm

Exercise 13.1 | Surface Area of Cubes & Cuboids

1. Class 9 Exercise 13.1 Question 3 | Height of hall ▶
2. Class 9 Exercise 13.1 Question 6 | TSA of Herbarium ▶
3. Class 9 Exercise 13.1 Question 7 | Shanti Sweets ▶

Exercise 13.2 | Surface Area of Cylinders

1. Class 9 Exercise 13.2 Question 3 | CSA TSA of Metal Pipe ▶
2. Class 9 Exercise 13.2 Question 4 | Roller & Playground ▶
3. Class 9 Exercise 13.2 Question 9 | Cylindrical Petrol Tank ▶
4. Class 9 Exercise 13.2 Question 10 | CSA of Decorative Lampshade ▶

Exercise 13.3 | Surface Area of Cones

1. Class 9 Exercise 13.3 Question 5 | Length of Tarpaulin 3 m wide ▶
2. Class 9 Exercise 13.3 Question 8 | Cost of painting conical barricades ▶

Exercise 13.4 | Surface Area of Spheres & Hemispheres

1. Class 9 Exercise 13.4 Question 8 | Outer CSA of hemispherical bowl ▶
2. Class 9 Exercise 13.4 Question 9 | Surface area of sphere & Cylinder ▶