16. | Look at this series: 80, 10, 70, 15, 60, ... What number should come next? | |||||||
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17. | Look at this series: 2, 6, 18, 54, ... What number should come next? | |||||||
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18. | Look at this series: 5.2, 4.8, 4.4, 4, ... What number should come next? | |||||||
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19. | Look at this series: 8, 6, 9, 23, 87 , ... What number should come next? | |||||||
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