alleryএকটি দেওয়ালের জন্য দুইজন রাজমিস্ত্রির যথাক্রমে 14 এবং 21 দিন প্রয়োজন। একসাথে কাজ করলে তাদের প্রয়োজন
A8.4 দিন
B8 দিন
C7 দিন
D9 দিন
Answer & Solution
Correct answer: A. 8.4 দিন
প্রতিদিন 1/14 + 1/21 = 5/42 অংশ, তাই দেওয়ালটির জন্য সময় লাগে 42/5 = 8.4 দিন।
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