**Q1. Q is a point in the interior of a rectangle ABCD, if QA = 3 cm, QB = 4 cm and QC = 5 cm then the length of QD (in cm) is **

(a) 3√2

(b) 5√2

(c) √34

(d) √41

**Q2. The angles of a quadrilateral are in the ratio 1 : 2 : 3 : 4, the largest angle is: **

(a) 120°

(b) 134°

(c) 144°

(d) 150°

**Q6. Three cubes of sides 6 cm, 8 cm and 1 cm are melted to form a new cube. The surface area of the new cube is**

(a) 486 cm2

(b) 496 cm2

(c) 586 cm2

(d) 658 cm2

**Q7. If the area of the base of a cone is 770 cm^2 and the area of its curved surface is 814 cm2, then find its volume.**

(a) 213√5 cm^3

(b) 392√5 cm^3

(c) 550√5 cm^3

(d) 616√5 cm^3

**Q10. Two right circular cones of equal height and radii of their respective base 3 cm and 4 cm are melted together and made to a solid sphere of radius 5 cm. The height of a cone is**

(a) 10 cm

(b) 20 cm

(c) 30 cm

(d) 40 cm

**Q11. Each of the radius of the base and the height of a right circular cylinder is increased by 10%. The volume of the cylinder is increased by**

(a) 3.31%

(b) 14.5%

(c) 33.1%

(d) 19.5%

**Q12. If each edge of a cube is increased by 50%, the percentage increase in its surface area is**

(a) 150%

(b) 75%

(c) 100%

(d) 125%

**Q13. If the length of each side of a regular tetrahedron is 12 cm, then the volume of the tetrahedron is**

(a) 144√2 cu. cm,

(b) 72√2 cu. cm,

(c) 8√2 cu. cm,

(d) 12√2 cu. cm,

**Q14. The base of a right pyramid is a square of side 40 cm long. If the volume of the pyramid is 8000 cm3, then its height is:**

(a) 5 cm

(b) 10 cm

(c) 15 cm

(d) 20 cm

**SOLUTIONS**

**S2. Ans.(c)**

**Sol.**Angles be x, 2x, 3x, 4x

∴ x + 2x + 3x + 4x = 360°

⇒ 10x = 360° ⇒ x = 36°

∴ largest angle = 4x = 144°

**S3. Ans.(d)**

**Sol.**∠ACB = ∠DAC = 50° (Alternate interior ∠s)

∠BOC = 180° – 80° = 100°

∴ Now in ∆BOC,

∠DBC = 180° – (100° + 50°)

= 30°