A cement company earns a profit of Rs. 8 per bag of white cement sold ...
Given data:
Profit earned on selling 1 bag of white cement = Rs. 8
Loss incurred on selling 1 bag of grey cement = Rs. 5
Number of grey cement bags sold = 6,400
To find:
Number of white cement bags to be sold to have neither profit nor loss
Solution:
Let the cost price of 1 bag of white cement be x.
Selling price of 1 bag of white cement = cost price + profit
= x + 8
Selling price of 1 bag of grey cement = cost price - loss
= x - 5
Total cost price of 6,400 bags of grey cement = 6,400 * (x - 5)
For neither profit nor loss, the total selling price of white cement should be equal to the total cost price of grey cement.
Total selling price of white cement = number of white cement bags sold * selling price per bag
= n * (x + 8), where n is the number of white cement bags to be sold
Equating the total selling price of white cement to the total cost price of grey cement, we get:
n * (x + 8) = 6,400 * (x - 5)
nx + 8n = 6,400x - 32,000
nx - 6,392x = -32,000 - 8n
x(n - 6,392) = -32,000 - 8n
x = (-32,000 - 8n) / (n - 6,392)
Since x is the cost price of 1 bag of white cement, it should be a positive value. Therefore, we can assume that n > 6,392.
Now, we can check the options given and find the value of n that satisfies the condition n > 6,392 and gives a positive value of x.
(a) n = 2,000
x = (-32,000 - 8*2,000) / (2,000 - 6,392) = -72.67 (not possible)
(b) n = 3,000
x = (-32,000 - 8*3,000) / (3,000 - 6,392) = -29.33 (not possible)
(c) n = 5,000
x = (-32,000 - 8*5,000) / (5,000 - 6,392) = 80
(d) n = 4,000
x = (-32,000 - 8*4,000) / (4,000 - 6,392) = 20
Therefore, the correct option is (d) 4,000 bags of white cement should be sold to have neither profit nor loss.