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On a Sunday your parents took you to a fair. You could see lot of toys displayed and you wanted them to buy a Rubik's cube and a strawberry ice-cream for you.
Based on the information given above, answer the following questions :
(i) Find the length of the diagonal of Rubik's cube if each edge measures 6 cm.
(ii) Find the volume of Rubik's cube if the length of the edge is 7 cm.
(iii) (a) What is the curved surface area of hemisphere (ice-cream) if the base radius is 7 cm?
OR
(iii) (b) If two cubes of edges 4 cm are joined end-to-end, then find the surface area of the resulting cuboid.
Based on the information given above, answer the following questions :
(i) Find the length of the diagonal of Rubik's cube if each edge measures 6 cm.
(ii) Find the volume of Rubik's cube if the length of the edge is 7 cm.
(iii) (a) What is the curved surface area of hemisphere (ice-cream) if the base radius is 7 cm?
OR
(iii) (b) If two cubes of edges 4 cm are joined end-to-end, then find the surface area of the resulting cuboid.
Show SolutionHide Solution↓
(i) Length of diagonal of cube = $\sqrt{3} \times \text{side}$
$= 6\sqrt{3} \text{ cm}$ (1 Mark)
(ii) Volume of Rubik's cube = $(7)^3$
$= 343 \text{ cm}^3$ (1 Mark)
(iii) (a) CSA of hemisphere = $2 \times \frac{22}{7} \times 7 \times 7$
$= 308 \text{ cm}^2$ (1 Mark)
OR
(iii) (b) Surface area of resulting cuboid = $5(4)^2 + 5(4)^2$
$= 160 \text{ cm}^2$ (1 Mark)
ALTERNATE SOLUTION :
(iii) (b) Surface area of resulting cuboid = $2( 8\times 4 + 4 \times 4 +8\times4)$
$= 160 \text{ cm}^2$ (1 Mark)
$= 6\sqrt{3} \text{ cm}$ (1 Mark)
(ii) Volume of Rubik's cube = $(7)^3$
$= 343 \text{ cm}^3$ (1 Mark)
(iii) (a) CSA of hemisphere = $2 \times \frac{22}{7} \times 7 \times 7$
$= 308 \text{ cm}^2$ (1 Mark)
OR
(iii) (b) Surface area of resulting cuboid = $5(4)^2 + 5(4)^2$
$= 160 \text{ cm}^2$ (1 Mark)
ALTERNATE SOLUTION :
(iii) (b) Surface area of resulting cuboid = $2( 8\times 4 + 4 \times 4 +8\times4)$
$= 160 \text{ cm}^2$ (1 Mark)