Cost of bananas is increased by rupees per dozen one can get two dozen less for 840 rupees find the cost of one dozen

Let the cost of banana per dozen be Rs. x.

Amount for which bananas are bought = Rs. 840

No. of dozens of bananas for Rs 840  = 840/x

New cost of banana per dozen = Rs. (x + 1)

New No. of dozens of bananas for Rs 840 = 840/x+1

According to given condition,

840/x – 840 / x + 1 = 2

∴ 840[1/x – 1/x+1] = 2

∴ 840 [x+1- x / x(x+1)] = 2

∴ 840 [1/ (x² + x)] = 2

∴ 840 = 2(x² + x)

∴ 2x2 + 2x – 840 = 0

Dividing by 2, we get

x² + x – 420 = 0

x² – 20x + 21x – 420 = 0

∴  x (x – 20) + 21 (x – 20) = 0

∴  x – 20 = 0 or x + 21 = 0

∴  x = 20 or x = –21

∴  The cost of bananas cannot be negative.

∴  x = 20

The original cost of one dozen banana is Rs. 20

hope it helps you

Step-by-step explanation:

10 glasses of juice could be made with 5 carrots, 1,500 orange juice, 2,000 papaya juice.