Area Problems A tank is 25m long 12m wide and 6m deep. The cost of plastering its walls and bottom at 75 paise per sq m is Rs. 558 Rs. 358 Rs. 258 Rs. 458 Rs. 558 Rs. 358 Rs. 258 Rs. 458 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Area to be plastered = 2 l + b × h + l × b = 2 25 + 12 × 6 + 25 × 12 = 744 s q . m Cost of plastering = 744 × 75 100 = R s . 558
Area Problems If the diagonal of a rectangle is 17cm long and its perimeter is 46 cm. Find the area of the rectangle. 120 130 140 110 120 130 140 110 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP let length = x and breadth = y then 2(x+y) = 46 => x+y = 23 x²+y² = 17² = 289 now (x+y)² = 23² => x²+y²+2xy= 529 => 289+ 2xy = 529 => xy = 120 area = xy = 120 sq.cm
Area Problems If the circumference of a circle is the 352 meters, then its area in m square is? 5986 8956 6589 9856 5986 8956 6589 9856 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP circumference = 2?r = 2 x (22 / 7) x r = 352? r = (352 x 7) / (22 x 2) =56 cmNow area = ?r2 = (22 / 7) x 56 x 56 m2= 9856 m2
Area Problems How many circular plates of diameter d be taken out of a square plate of side 2d with minimum loss of material? 2 8 6 5 2 8 6 5 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Area of square plate = (Side)2 = (2d)2= 4d2Area of circular plate = ? (d/2)2= ?d2/4? Number of square plates = [(4d2)/4] / [(?d2)/4]= (4 x 4)/? ? 5Since, nearest integer value is 5.
Area Problems The area of the largest circle that can be drawn inside a rectangle with sides 18cm by 14cm is 378 49 1078 154 378 49 1078 154 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP The diameter is equal to the shortest side of the rectangle. So radius= 14/2 = 7cm. Therefore, area of circle = (r)2 = (22/7) x 49 = 154 cm2
Area Problems The area of a right angled triangle is 10 sq cm. If its perpendicular is equal to 20 cm, find its base. 4 cm 2 cm 3 cm 1 cm 4 cm 2 cm 3 cm 1 cm ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Given that, area = 10 sq cm, perpendicular = 20 cm and base = ? area = (base x Perpendicular) / 2 ? 10 = (base x 20) / 2 ? base = 1 cm
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