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In a lab in Hyderabad, the bacteria in a dish double every hour, as the pictures show. Each dot stands for 500 bacteria. How many bacteria will there be 4 hours after the start?

Class 8Compound InterestComparing Quantities
  • A12,000
  • B7,500
  • C24,000
  • D48,000

Step-by-Step Solution

At the start there are 3 dots bacteria. Doubling 4 times: . (12,000 is after 3 hours; 7,500 adds 1,500 each hour.)
Answer: C) 24,000

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