Question
A shopkeeper give 4 articles free on the purchase of
every 12 articles. He also allows a discount of 20% to customer and still earns 20% profit. Find the ratio of cost price to mark price of the article.Solution
Buy 12 get 4 free,% discount offered = [4/(12 + 4)] ×100 = 4/16×100 = 100/4 = 25% So final Offer(discount) = Buy 12 get 4 free + 20% discount = 25% discount +20% discount So net discount = a + b - ab/100 = 25 +20 – (25 × 20/100) = 45 – 5 = 40% Let MP = 100 SP = (100-40% discount on MRP ) = 100 -40 = 60 Profit = 20% = 1/5 So CP = 50 CP∶ MP = 50∶ 100 = 1∶ 2 Alternate Method 
The perimeter of a rectangle of length 2(x + 5) cm and breadth 2(x + 2) cm is double the perimeter of a square of area 324 cm². Find the area of the re...
Find the surface area of the smallest cube that can perfectly fit a sphere of volume 36000π cm3 inside it.
The length of a rectangle is 64 cm. If the ratio of length to perimeter of the rectangle is 4:15, find the area of a circle whose diameter is 6 cm less ...
The length, breadth and height of a room are 8m, 10m and 12m respectively. Find the cost of white washing the room at the rate of Rs 15 per m²?
If the volume of a cylinder is 180π and the ratio of radius to its height is 6:5 then find the curved surface area of cylinder?
The volume of a cube is 512 cm³. If the cost of painting the cube is Rs. 6 per cm², then find the cost of painting five faces of the cube.
A cylindrical tank is filled at the rate of 6 liters per minute. If the tank is 2 meters tall and has a radius of 50 cm, how long will it take to fill t...
A square’s side is 25% less than the length of a rectangle. The area and breadth of the rectangle are 2000 cm² and 40 cm respectively. Calculate the ...
The ratio of length to breadth of a rectangle is 5:4, respectively. Perimeter of rectangle is 252 cm. If each side of a square is 25% more than the brea...
If the side of square and its area is in the ratio of 10:35 then find its perimeter?