Subject
Quantitative Aptitude
Topic
Speed & Distance
A man travels from A to B at 20 km/hr. He makes the return journey at 30 km/hr. What was his average speed?
A man travels from A to B at 20 km/hr. He makes the return journey at 30 km/hr. What was his average speed?
ক)
20খ)
22গ)
23ঘ)
25ঙ)
None of theseExplanation
QUESTION : একজন ব্যক্তি A থেকে B পর্যন্ত 20 km/hr গতিতে যাত্রা করে। সে ফেরার পথে 30 km/hr গতিতে আসে। তার গড় গতি কত ছিল? সমাধান: *ধরি, A থেকে B-এর দূরত্ব x km। -A থেকে B যাওয়ার সময় = x ÷ 20 ঘণ্টা -B থেকে A ফেরার সময় = x ÷ 30 ঘণ্টা *মোট সময় = (x ÷ 20) + (x ÷ 30) = (3x + 2x) ÷ 60 = 5x ÷ 60 ঘণ্টা *মোট দূরত্ব = 2x km (যাওয়া-আসা) *গড় গতি = মোট দূরত্ব ÷ মোট সময় - 2x ÷ (5x ÷ 60) - (2x × 60) ÷ 5x - 24 km/hr -সুতরাং, ব্যক্তিটির গড় গতি 24 km/hr। সঠিক উত্তর: (E) None of these (কারণ 24 km/hr দেওয়া অপশনগুলোর মধ্যে নেই)Related questions
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