Area Problems The length of a rectangular plot is 20 metres more than its breadth. If the cost of fencing the plot @ 26.50 per metre is Rs. 5300, what is the length of the plot in metres? 40 Data inadequate 120 None of these 40 Data inadequate 120 None of these ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let breadth = x metres. Then, length = (x + 20) metres. Perimeter = ❨ 5300 ❩ m = 200 m. 26.50 ∴ 2[(x + 20) + x] = 200 ⟹ 2x + 20 = 100 ⟹ 2x = 80 ⟹ x = 40. Hence, length = x + 20 = 60 m
Area Problems The radius of the wheel of a vehicle is 70 cm. The wheel makes 10 revolutions in 5 seconds. The speed of the vehicle is? 29.46 km/hr. 32.72 km/hr. 31.68 km/hr. 36.25 km/hr. 29.46 km/hr. 32.72 km/hr. 31.68 km/hr. 36.25 km/hr. ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Circumference = 2?r = 2 x (22 / 7) x 70 cm = 440 cm Distance travelled in 10 revolutions = 440 x 10 cm = 4400 cm = 44 m? Speed = distance / time= 44 / 5 m/sec= (44 / 5) x (18 / 5) km/hr = 31.68 km/hr
Area Problems The diagonals of two squares are in the ratio of 3 : 2. Find the ratio of their areas. 9 : 5 9 : 7 9 : 2 9 : 4 9 : 5 9 : 7 9 : 2 9 : 4 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the diagonals of the squares be 3x and 2x.? Ratio of their areas = [(1/2) (3x2)] / [(1/2) (2x2)] = 9/4
Area Problems The wheel of an engine turns 350 times round its axle to cover a distance of 1.76 km. The diameter of the wheel is 3 cm 9 cm ?3 cm 3?3 cm 3 cm 9 cm ?3 cm 3?3 cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Distance covered in 1 round = (Total Distance) / (Total round)= (1.76 x 1000)/350= 176/35 m ? 2?r = (1.76 x 100) / 35 cm2? = Diameter = 17600 x 7/22 x 35 = 160 cm
Area Problems In a circle of radius 21 cm an arc subtends an angle of 72° at the centre. The length of the arc is? 21.6 cm 26.4 cm 13.2 cm 19.8 cm 21.6 cm 26.4 cm 13.2 cm 19.8 cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Arc length = 2?r (?° / 360°) = 2 x (22/7) x 21 x (72° / 360°) cm= 26.4 cm
Area Problems What is the area of a square having perimeter 68 cm? 361 sq cm 284 sq cm 289 sq cm 269 sq cm 361 sq cm 284 sq cm 289 sq cm 269 sq cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP According to the question,4a = 68 [ where a = side]?a = 68/4 = 17 cm? Required area = a2= (17)2 = 289 sq cm