Answer:
. (a) A scientist is doing an experiment on bacteria. She finds that the number ofbacteria in a test tube increase at a rate of 0.9% per hour.At 12 noon there are 4500 bacteria.At 3 pm, how many bacteria will be present? Give your answer to 3 significantfigures.
12pm 4500 bacteria1pm 4500 x 1.009 bacteria 2pm 4500 x 1.009 x 1.009 bacteria3pm 4500 x 1.009 x 1.009 x 1.009 bacteriaTherefore at 3pm there are 4620 bacteria present.
Answer: 4620 (3)(b) In another experiment with the same bacteria, the scientist counts 3000 bacteria.How many bacteria were there two hours prior to this measurement?Give your answer to 3 significant figures.
Now 3000 bacteria1 hour ago 3000 ÷ 1.009 bacteria 2 hours ago 3000 ÷ 1.009 ÷ 1.009 bacteriaTherefore 2 hours ago there were 2950 bacteria present
Answer: 2950
Step-by-step explanation:
