Subject
Quantitative Aptitude
Topic
Speed & Distance
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?
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?
ক)
35খ)
34.3গ)
37.5ঘ)
35.3ঙ)
36Explanation
QUESTION : Sonia Uttara থেকে IBA যায় car-এ 40 km per hour speed-এ এবং ফিরে আসে auto rickshaw-তে 30 km per hour speed-এ। তার পুরো journey-র average speed কত km/hour? -এখানে মূল বিষয় হল, average speed হিসাব করার জন্য আমাদের মোট দূরত্ব এবং মোট সময় জানতে হবে। -যদিও আমরা Uttara থেকে IBA-র দূরত্ব জানি না, আমরা এটিকে x ধরে নিতে পারি। -যাওয়ার সময় হবে x/40 ঘণ্টা, আর ফেরার সময় হবে x/30 ঘণ্টা। -মোট দূরত্ব হবে 2x (যাওয়া-আসা মিলিয়ে)। -Average speed formula অনুযায়ী, আমরা মোট দূরত্বকে মোট সময় দিয়ে ভাগ করব। -হিসাব করে পাই, average speed = 34.29 km/hour, যা প্রায় 34.3 km/hour। -তাই, Sonia-র পুরো journey-র average speed হল 34.3 km/hour, -যা option (B)-তে দেওয়া আছে।Related questions
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