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Q9) Area of a triangle is 162 sq.cm. It's base is 36 cm. Find its altitude. 1) 9 cm 2) 4.5 cm 3) 6 cm 4) 8 cm Let h be altitude of the triangle. (1/2)×36×h = 162 h = 9 cm Hence, option 1. Q10) The ratio between the perimeter and the length of the rectangle is 5:2. Then what is the ratio of breadth to the length of the rectangle? 1) 4:5 2) 1:4 3) 2:3 4) None of these P/L = 5/2 2(L + B)/L = 5/2 4(L + B) = 5L 4B = L B/L = 1/4 Hence, option 2. Q11) Two opposite parallel sides of a trapezium are 5 cm and 7 cm and its area is 48 cm2. Find the distance between the parallel sides? 1) 8 cm 2) 6 cm 3) 12 cm 4) 4 cm Let h be the distance between the parallel sides if a trapezium. 48 = (1/2)(5 + 7)h On solving, h = 8 cm Hence, option 3. Q12) Area of the rectangle is 15 sq. cm and its diagonal is √34. The perimeter of the rectangle is: 1) 8 cm 2) 20 cm 3) 12 cm 4) 16 cm √L2 + B2 = √34 L2 + B2 = 34 (L + B)2 = L2 + B2 + 2LB (L + B)2 = 34 + 2(15) = 64 L + B = 8 ∴ Perimeter of the rectangle = 2(L + B) = 16 cm Hence, option 4. |