Select all sequences that could be geometric.
2, 4, 7, 11, . . .
\(\frac13\), 1, 3, 9, . . .
1, 3, 5, 7, . . .
\(\frac12\), 2, 8, 32, . . .
1,000, 200, 40, 8, . . .
999, 899, 799, 699, . . .
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Problem 2
A blogger had 400 subscribers to her blog in January. The number of subscribers has grown by a factor of 1.5 every month since then. Write a sequence to represent the number of subscribers in the 3 months that followed.
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Problem 3
Tyler says that the sequence 1, 1, 1, . . . of repeating 1s is not exponential because it does not change. Do you agree with Tyler? Explain your reasoning.
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Problem 4
In 2000, an invasive plant species covered 0.2% of an island. For the 5 years that followed, the area covered by the plant tripled every year.
A student said, “That means that about half of the island’s area was covered by the plant in 2005!”
Do you agree with his statement? Explain your reasoning.
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Problem 5
A square picture with a side length of 30 cm is scaled, using a photocopier, so that the side lengths are reduced to 60% of their previous length. The copy is then scaled by 60% again.
What is the side length of the second copy of the picture?
What is the side length of the picture after it has been scaled by 60% 4 times? Show your reasoning.
