The Dedicated Freight Corridor Corporation of India Limited (DFCCIL) has released the DFCCIL Junior Executive Result for Mechanical and Signal & Telecommunication against Advt No. 04/2021. Candidates who are qualified for the CBT round of the DFCCIL Junior Executive are eligible for the Document Verification & Medical Examination. The highest marks of the UR category for Mechanical are 103.50 and for Signal & Telecommunication 98.750. With a salary range between Rs. 25,000 to Rs. 68,000, it is a golden opportunity for all job seekers.
In order to continue enjoying our site, we ask that you confirm your identity as a human. Thank you very much for your cooperation. A key part of solving these types of problems is keeping track of how much 'pure' stuff you need. You need 1080 mL of 50% solution = .5*1080 = 540 mL of pure acid. . x = volume of 70% acid you will use y = volume of 30% acid you will use . BUT since you know x+y = 1080, it is better to define the volumes in terms of 'x' only . y = 1080-x . Set up an equation that will describe the two parts and the final result . .7x + .3(1080-x) = .5*1080 . multiply by 10 to get rid of decimals 7x + 3(1080-x) = 5*1080 = 5400 . expand, collect, simplify... . 7x + 3240 - 3x = 5400 4x = 2160 x = 540 . y = 1080 - 540 = 540 . So our proposed solution is 540 mL of 70% acid and 540 mL of 30% solution. By inspection that makes sense because (.7+.3)/2 = .5 But we need to check our work...always... . How much 'pure' acid will be in the final solution compared to how much you need. You need 540 mL. . .7*540 = 378 .3*540 = 162 378 + 162 = 540 Correct! . Answer: You need to mix 540 mL of 70% acid with 540 mL of 30% acid to produce 1080 mL of 50% acid. . Done Treena P. What quantity of 70 per cent acid solution must be mixed with a 25 per cent solution to produce 432 mL of a 50 per cent solution? 1 Expert Answer We know that x ml of 70% solution + (432-x) ml of 25% solution yields 432 ml of 50% solution. So... 0.70 (x) + 0.25 (432-x) = 0.50 (432) 0.70 x + (108 - 0.25 x) = 216 0.70 x + 108 - 0.25 x = 216 0.45 x = 108 x = 240 So 240 ml of 70% solution + 192 ml (432-240) of 25% solution yields 432 ml of 50% solution. Check: (240 * 0.70) + (192 * 0.25) = (432 * 0.50) |