Question
A mixture contains ‘X’ liter milk and ‘Y’ liter
water. If 30 liter of mixture is taken out and replaced with water, then the quantity of milk and water becomes equal. But, if 60 liter of mixture is taken out and replaced with water, then quantity of milk becomes half of the quantity of water. Find the value of X and Y.Solution
Mixture contains total (X + Y) liters ATQ, X– [30X/((X+Y))] = Y– [30Y/(X+Y)]+30  X² + XY – 30X = XY + Y² – 30Y + 30X + 30Y ⇒ X² – Y² = 60X…(i) And, 2[X–60X/(X+Y)]=[Y–60Y/(X+Y)+60] 2X² + 2XY – 120X = XY + Y² – 60Y + 60X + 60Y  2X2+ XY = 180X +Y2  …(ii) Subtract (i) from (ii) X² + XY = 120X  X + Y = 120ℓ   …(iii) But X² – Y² = 60X ⇒ (X + Y) (X – Y) = 60X ⇒ 2 (X – Y) = X ⇒ 2X – 2Y = X ⇒ X = 2Y   …(iv) By using (iii) & (iv) ⇒ Y = 40ℓ And X = 80ℓ
A candidate who gets 24% marks fails by 12 marks but another candidate who gets 46% marks gets 14% more than the passing marks. Find the maximum marks.
Find the rate of interest if amount after 2 years on simple interest on a capital of Rs 1000 is Rs 1200.
Due to recession in the company number of employees decreased by 12.5%, but the working time of employees increased by 2 hrs, so that the production of ...
- Initially, Meena had a salary of Rs. 45,000 and her expenses to savings were in the ratio 5:4. After her salary increase, she spent 10% less and saved 50% ...
If two successive discounts of 20% and 12% are applied, what would be the equivalent single discount?
270 candidates appeared for an examination, of which 252 passed. The pass percentage is :
...- A farmer harvested 8000 kg of produce, where 40% of the produce was fruits and the remaining was vegetables. If 60% of the fruits harvested and 50% of the ...
- The total of two numbers ‘u’ and ‘v’ is 600. If ‘u’ is reduced by 12% and ‘v’ is increased by 18%, both become equal. Find the value of ‘...
The population of a town increases by 20% per annum. If the population after 2 years is 43,200, find its present population.
810 sweets were distributed equally among children in such a way that the number of sweets received by each child is 40% of the total number of children...