Subject
Quantitative Aptitude
Topic
Speed & Distance
A man drives 150 km to the seashore in 3 hours 20 min. He returns from the shore to the starting point in 4 hours 10 min. Let r be the average rate for the entire trip. Then the average rate for the trip going exceeds, in kilometers per hour, by ( একজন লোক 3 ঘন্টা 20 মিনিটে 150 কিলোমিটার পথ গাড়িতে চড়ে সমুদ্র সৈকতে আসে । সৈকত থেকে পূর্বের জায়গায় ফেরত আসতে লোকটির 4 ঘন্টা 10 মিনিট লাগলো । যদি , পুরো ভ্রমণের গড় গতি r হয়, যাওয়ার সময়ের গতি r থেকে কত (km/hr) বেশী হবে ?)
A man drives 150 km to the seashore in 3 hours 20 min. He returns from the shore to the starting point in 4 hours 10 min. Let r be the average rate for the entire trip. Then the average rate for the trip going exceeds, in kilometers per hour, by ( একজন লোক 3 ঘন্টা 20 মিনিটে 150 কিলোমিটার পথ গাড়িতে চড়ে সমুদ্র সৈকতে আসে । সৈকত থেকে পূর্বের জায়গায় ফেরত আসতে লোকটির 4 ঘন্টা 10 মিনিট লাগলো । যদি , পুরো ভ্রমণের গড় গতি r হয়, যাওয়ার সময়ের গতি r থেকে কত (km/hr) বেশী হবে ?)
ক)
2খ)
4গ)
4(1/2)ঘ)
5Explanation
লোকটির সৈকত যেতে সময় লেগেছে = 3 ঘন্টা 20 মিনিট = 3 (1/3) = (10/3) ঘন্টা যাওয়ার সময় গতি = {150/(10/3)} = 45 km/hr ফিরতে সময় লেগেছে = 4 ঘন্টা 10 মিনিট = 4 (1/6) = (25/3) ঘন্টা ফেরার সময় গতি = {150/(25/6)} = 36 km/hr ∴ গড় গতিবেগ, r = {(2×45×36)/(45+36)} = 40 km/hr ∴ পার্থক্য = (45-40) = 5 km/hrRelated questions
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