Subject
Quantitative Aptitude
Topic
Speed & Distance
A is faster than B. A and B each walk 24 km. The sum of their speeds is 7 km/hr and the sum of times taken by them is 14 hours. Then, A's speed is equal to ( A, B অপেক্ষা দ্রুততর । A এবং B প্রত্যেকে 24 কিলোমিটার হাঁটে । তাদের গতির সমষ্টি 7 km/hr এবং তাদের অতিক্রান্ত সময় এর সমষ্টি 14 ঘন্টা হলে, A এর গতি কত ?)
A is faster than B. A and B each walk 24 km. The sum of their speeds is 7 km/hr and the sum of times taken by them is 14 hours. Then, A's speed is equal to ( A, B অপেক্ষা দ্রুততর । A এবং B প্রত্যেকে 24 কিলোমিটার হাঁটে । তাদের গতির সমষ্টি 7 km/hr এবং তাদের অতিক্রান্ত সময় এর সমষ্টি 14 ঘন্টা হলে, A এর গতি কত ?)
ক)
3 km/hrখ)
4 km/hrগ)
5 km/hrঘ)
7 km/hrExplanation
ধরি, A এর গতি x km/hr তাহলে, B এর গতি = ( 7 - x ) km/hr তাদের সময়ের সমষ্টি = [(24/x) + {24/(7-x)}] শর্তমতে, (24/x) + {24/(7-x)} = 14 =>[{24(7-x)+24x/{x(7-x)}] = 14 => 24(7-x) + 24x = 14x(7-x) => 14x 2 - 98x + 168 = 0 => x 2 - 7x + 12 = 0 => (x-3) (x-4) = 0 ∴ x = 3 or x = 4 3+4 = 7 যেহেতু A এর বেগ B এর চেয়ে বেশি সুতরাং x = 4 km/hrRelated questions
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