Subject
Quantitative Aptitude
Topic
Speed & Distance
A car traveled 75% of the way from town A to town B at an average speed of 50 miles/hour. The car travels at an average speed of S miles/hour for the remaining part of the trip. The average speed for the entire trip was 40 miles/hour. What is S?
A car traveled 75% of the way from town A to town B at an average speed of 50 miles/hour. The car travels at an average speed of S miles/hour for the remaining part of the trip. The average speed for the entire trip was 40 miles/hour. What is S?
ক)
10খ)
20গ)
25ঘ)
30ঙ)
37.5Explanation
QUESTION : একটি গাড়ি town A থেকে town B-এর দিকে যাত্রার 75% পথ 50 miles/hour গড় গতিতে অতিক্রম করে। বাকি অংশের জন্য গাড়িটি S miles/hour গড় গতিতে চলে। সম্পূর্ণ যাত্রার গড় গতি ছিল 40 miles/hour। S এর মান কত? সমাধান: *চলক নির্ধারণ: -ধরি, মোট দূরত্ব x miles। *দূরত্ব নির্ণয়: -যাত্রার প্রথম অংশ = 0.75x miles -যাত্রার দ্বিতীয় অংশ = 0.25x miles *সময় নির্ণয়: -প্রথম অংশের সময় = 0.75x / 50 ঘণ্টা -দ্বিতীয় অংশের সময় = 0.25x / S ঘণ্টা -মোট সময় = x / 40 ঘণ্টা (দেওয়া গড় গতি অনুযায়ী) *সমীকরণ স্থাপন: -(0.75x / 50) + (0.25x / S) = x / 40 *S এর মান নির্ণয়: -0.015x + 0.25x/S = 0.025x -0.25x/S = 0.01x -0.25/S = 0.01 -S = 0.25/0.01 = 25 অতএব, সঠিক উত্তর হল (C) 25 miles/hour।Related questions
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