9514 1404 393
Answer:
7. a[n] = 3·a[n-1]; 56.7, 170.1, 510.3
8. a[n] = 5·a[n-1]; 81.25, 406.25, 2031.25
9. a[n] = 0.02·a[n-1]; 0.00000032, 0.0000000064, 0.000000000128
10. a[n] = 0.3·a[n-1]; 0.0486, 0.01458, 0.004374
Step-by-step explanation:
These sequences are all geometric sequences, so terms have a common ratio. That ratio can be found by dividing the second term by the first. The next term is found by multiplying the last term by the common ratio.
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7. ratio is 2.1/0.7 = 3. Each term is 3 times the last. The next three terms are ...
18.9×3 = 56.7, then 170.1 and 510.3
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8. ratio is .65/.13 = 5. Each term is 5 times the last. The next three terms are ...
16.25×5 = 81.25, then 406.25 and 2031.25
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9. ratio is .04/2 = .02. Each term is 0.02 times the last. The next three are ...
0.000016×0.02 = 0.00000032 = 3.2×10^-7, then 6.4×10^-9 and 1.28×10^-10
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10. ratio is 1.8/6 = 0.3. Each term is 0.3 times the last. The next three are ...
0.162×0.3 = 0.0486, then 0.01458 and 0.004374
