SSC CHSL Tier-1 practice question
A bacteria culture starts with 1 bacterium in a petri dish and doubles in number every hour. How many bacteria will be present after 7 hours?
From a SSC CHSL Tier-1 Quantitative Aptitude practice set · Quantitative Aptitude
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Correct answer: (C) 128
After each hour the count is multiplied by 2, so after 7 hours the count is 1 × 27 = 128 (since an means a multiplied by itself n times). Thus 27 = 128 bacteria.
हिंदी में प्रश्न
एक पेट्री डिश में जीवाणु संवर्धन 1 जीवाणु से शुरू होता है और हर घंटे इसकी संख्या दोगुनी हो जाती है। 7 घंटे बाद कितने जीवाणु होंगे?
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सही उत्तर: (C) 128
हर घंटे संख्या 2 से गुणा होती है, इसलिए 7 घंटे बाद संख्या 1 × 27 = 128 होगी (क्योंकि an का अर्थ है a को स्वयं से n बार गुणा करना)। अतः 27 = 128 जीवाणु।
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