Question
Area of a rectangle is equal to the total surface area
of a hemisphere having volume 4394 cm³ . Find the perimeter of the rectangle if its length is 125% more than its breath. (Take π = 3)Solution
Let, the radius of the hemisphere be ‘r’ cm. So according to question: 2/3 × 3 × r3 = 4394 r3 = 2197 r = 13 So, the total surface area of the hemisphere = 3 × π × 13² = 3 × 3 × 13² = 1521 cm² Let the breadth of the rectangle be ‘x’ cm So the length of the rectangle = 2.25x cm According to question: x × 2.25x = 1521 x² = 676 x = 26 So the breadth of the rectangle = 26 cm Length of the rectangle = 26 × 2.25 = 58.5 cm So the perimeter of the rectangle = 2 × (58.5 + 26) = 169 cm
- A school has 720 students. The ratio of boys to girls is 4:2. Among the boys, the passed to failed ratio is 9:3. Among the girls, the passed to failed rati...
Ravi divided a sum of money among Aryan, Kiran and Rohan in the ratio 5:7:13 respectively. 70% of Aryan’s share is Rs. 210 less than 50% of Rohan’s ...
In what proportion must a grocer mix sugar at Rs.12 a kg and Rs.7 a kg so as to make a mixture worth Rs.8 a kg ?
The ratio of number of girls to number of boys is 3 : 2 in a class of 60 students. The average marks scored by the boys in Physics is 72 and the average...
The ratio of the ages of A and B is 3:5. If the difference between their ages is 10 years, what is the sum of their ages?
A bag contains coins of ₹2, ₹1 and 50 paise in the ratio 4:6:8. If the total money in the bag is ₹576, how many 50-paise coins are there?
The incomes of A and B are in the ratio of 3:2 and their expenditures are Rs. 14,000 and Rs. 10,000 respectively. If A saves Rs. 7000, then B's savings ...
In an alloy of three metals, ratio of the quantity of gold, silver and platinum is 5:6:8, respectively. If total quantity of silver and platinum togethe...
The total number of students to the total number of teachers in Universities A and B is in the ratio 25:4. Additionally, the number of teachers in Univ...Ram, Laxman, Bharat and Shatrughan purchase a plot for Rs. 54,00,000. The share of Laxman + Bharat + Shatrughan is 440% of Ram and the Share of Ram + B...