Subject
Quantitative Aptitude
Topic
Speed & Distance
A can complete a journey in 10 hours. He travels first half of the journey at the rate of 21 km/hr and second half at the rate of 24 km/hr. Find the total journey in km. ( A একটি যাতা 10 ঘন্টায় সম্পন্ন করতে পারে । সে যাত্রার অর্ধেক পথ 21 km/hr গতিতে এবং বাকি অর্ধেক পথ 24 km/hr গতিতে অতিক্রম করে তাহলে, মোট দূরত্ব কত কিলোমিটার ?)
A can complete a journey in 10 hours. He travels first half of the journey at the rate of 21 km/hr and second half at the rate of 24 km/hr. Find the total journey in km. ( A একটি যাতা 10 ঘন্টায় সম্পন্ন করতে পারে । সে যাত্রার অর্ধেক পথ 21 km/hr গতিতে এবং বাকি অর্ধেক পথ 24 km/hr গতিতে অতিক্রম করে তাহলে, মোট দূরত্ব কত কিলোমিটার ?)
ক)
220 kmখ)
224 kmগ)
230 kmঘ)
234 kmExplanation
ধরি, মোট পথ x km প্রথম (x/2) km যায় 21 km/h বেগে ∴ সময়, t 1 = {(x/2)/21} hr [ সময় = দূরত্ব/বেগ ] শেষ (x/2) km যায় 24 km/hr বেগে সময়, t 2 ={ (x/2)/24 } [ সময় = দূরত্ব/বেগ] মোট সময় = t 1 + t 2 = 10 শর্তমতে,[ {(x/2)/21} + {(x/2)/24} ] = 10 => (x/42) + (x/48) = 10 => {(8x+7x)/336} = 10 => 15x = 336×10 ∴ x ={ (336×10)/15 }= 224 kmRelated questions
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