Instructions: DO NOT USE CALCULATOR. Figures are not drawn to scale. Kalam takes 2 days more than what Zakir takes to produce x chairs. They work together for 6 days and produce 24x chairs. How many days will it take Kalam to produce 2x chairs?
A. 2
B. 4
C. 5
D. 6
E. none of these
Explanation: (E) Let \(D_Z\) be the days Zakir takes to produce x chairs, so \(D_K = D_Z + 2\). Work Rate: \(R_Z = \frac{x}{D_Z}\) chairs/day, \(R_K = \frac{x}{D_K} = \frac{x}{D_Z + 2}\) chairs/day. Combined rate: \(R_{Z+K} = \frac{24x}{6} = 4x\) chairs/day. \(R_{Z+K} = R_Z + R_K \implies 4x = \frac{x}{D_Z} + \frac{x}{D_Z + 2}\). Divide by x: \(4 = \frac{1}{D_Z} + \frac{1}{D_Z + 2} \implies 4 = \frac{D_Z + 2 + D_Z}{D_Z(D_Z + 2)} = \frac{2D_Z + 2}{D_Z^2 + 2D_Z}\). \(4(D_Z^2 + 2D_Z) = 2D_Z + 2 \implies 4D_Z^2 + 8D_Z = 2D_Z + 2 \implies 4D_Z^2 + 6D_Z - 2 = 0 \implies 2D_Z^2 + 3D_Z - 1 = 0\). Solving this quadratic equation for \(D_Z\) yields an irrational number. \(D_K = D_Z + 2\) is also irrational. Days for Kalam to produce 2x chairs: \(D_{K(2x)} = D_K \cdot 2 = 2(D_Z + 2)\), which is an irrational number. Since the options are integers, the answer is none of these.
Related Questions (Any University/Year)
- ১১ জন কুমোর ৪ দিনে ১৪৩টি হাড়ি তৈরি করতে পারে। ৪ দিনে ১৬৯টি হাড়ি তৈরি করতে কত জন কুমোরের প্রয়োজন?
- Sonia travels to IBA from Uttara by car at a speed of 40 km per hour and returns to Uttara at a speed of 30 km per hour by an auto rickshaw. What is her average speed in the entire journey in km/hour?
- In a class of 78 students 41 are taking French, 22 are taking German. One of the students taking French or German, 9 are taking both courses. How many students are not enrolled in either course?
- If 4 is subtracted from one-fourth of a number, the result is 20. Which of the following is the number?
- একটি ঝুড়িতে আপেল এবং কমলা মিলিয়ে ৩৩টি ফল আছে। প্রতিটি আপেল এবং কমলা ১৮ টাকা দরে কেনা হয়েছে। সবগুলো ফল কিনতে যদি ৫৯৪ টাকা খরচ হয় এবং আপেল এর চাইতে ৫টি কমলা কম থাকে তবে ঝুড়িতে কয়টি আপেল ছিল?
- The electric company charge: Tk 0.3 per KWH. Rahim used 2800 KWH in April, 3200 KWH in May, and 3600 KWH in June. What was his average costs of electricity in taka for the 3 months?
- In TownshipK each property is taxed at 8 percent of its assessed value. If the value of a property in Township K is increased from $20,000 to $24,000, by how much will the property tax increase?
- A 112 meter rope is cut into three pieces with each piece twice as long as the previous one. How long is the longest piece?
- A trader incurs a loss of 10% from selling an item , if the selling price was taka 200 more he would have made a profit of 15% . What was the cost of the item ?
- A certain recipe calls for 3kgs of sugar for every 6 kgs of flour.If 60kgs of this sweet has to be prepared,how much sugar is required?
- Machine A can produce 40 bolts per minute, whereas machine B can produce only 30 per minute. Machine A begans along to make bolts but it breakdown after 1.5 minute and machine B must complete the job . If the job requires 300 bolts, how long does the whole operation take?
- The population of City X is 40% percent of the population of City Y. The population of City X is what percent of the total population of city X and City y together?
- If 12 men can build a wall 180 m long in 54 days ,how many days it will take to build a similar wall 160 m long ,if 16 men working on it
- 4 জন তাঁতী 4 দিনে 4টি মাদুর তৈরি করতে পারে। একই হারে ৪ জন তাঁতী ৪ দিনে কতটি মাদুর তৈরি করতে পারবে?
- একটি পাত্রে পানি ও সিরাপ ৩ঃ ৫ অনুপাতে মিশ্রিত রয়েছে । কতটুকু মিশ্রণ উঠিয়ে নিয়ে তার পরিবরর্ত পানি যুক্ত করলে তরল দুটির অনুপান ৫০ঃ৫০ হবে?
- একটি সংখ্যার ৭৫% এর সাথে ৭৫ যোগ করলে ফলাফল হিসেবে পূর্বের সংখ্যাটি পাওয়া যায়। সংখ্যাটি কত?
- A box in the university bookstore contains books and each book in the box is a History book. an English book or a and one -sixth are English books, what fraction of the books are Science books?
- Rahman is twice as old as Shermin. In y years Shermin will be 1.5 times older than she is now. What is Shermin's age?
- In the figure above area of the inscribed rectangle is 32. The circumference of the circle is-
- A large tanker can be filled by two by two pipes A and B in 60 minutes and 40 minutes respectively. How many minutes will it take to fill the tanker from empty state if B is used for half the time and A and B fill together for the other half?
- The cost of two litres of Oil and its container is Tk. 100. If the cost of the container is Tk. 23 less than the cost of one litre of Oil, what is the cost of one litre of Oil ?
- একটি ক্লাসে ৩০ জন শিক্ষার্থী আছে । তাদের মধ্যে ১৮ জন ফুটবল খেলে ও ১৪ জন ক্রিকেট খেলে । ৫ জন কিছুই খেলেনা । কত জন ফুটবল ও ক্রিকেট উভয়ই খেলে ?
- Reservoir A contains 450 million gallons of water more than does Reservoir B. If 100 million gallons of water were to be drained from Reseryoir A into Reservoir B, then Reservoir A would contain twice as much water as would Reservoir B. How many million gallons of water does reservoir A currently contain?
- Raisa took one cup of half olive-oil and half vinegar and poured it in a jar that had equal parts of olive-oil, vinegar, and water. If the result is a three-cup mixture of salad dressing, what portion of the dressing is olive-oil?
- Machine A produces bolts at a uniform rate of 120 every 40 seconds, and Machine B produces bolts at a uniform rate of 100 every 20 seconds. If the two machines run simultaneously, how many seconds will it take for them to produce total of 200 bolts?