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Bunuel
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A scientist placed ten bacteria cells in a glass jar. Every minute, th 10 Jul 2020, 03:50
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D
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25% (medium)

Question Stats:

75% (01:32) correct 25% (02:21) wrong based on 72 sessions

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A scientist placed ten bacteria cells in a glass jar. Every minute, the bacteria double in volume. After 20 minutes, the bacteria completely filled the glass jar. How many minutes did it take for the jar to be 25% full?

A. 4
B. 5
C. 10
D. 18
E. 19
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D
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Lipun
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A scientist placed ten bacteria cells in a glass jar. Every minute, th 10 Jul 2020, 05:24
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At end of 20 mins jar will be 100% full.
The jar will be 25% full just 2 mins prior to that. => At 18 mins jar will be 25% full.

Ans: D
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Vipul78
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A scientist placed ten bacteria cells in a glass jar. Every minute, th 10 Jul 2020, 05:41
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Hi Bunuel
The answer is D. But can you share the shortcut to solve this question here.

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yashikaaggarwal
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A scientist placed ten bacteria cells in a glass jar. Every minute, th 10 Jul 2020, 05:42
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A scientist placed ten bacteria cells in a glass jar. Every minute, the bacteria double in volume.

10 bacteria next minute will be 20..
And So On. ..

After 20 minutes, the bacteria completely filled the glass jar.
In 20th minute it's 100% full, Which is double of 50% which was the capacity of jar in 19th minute

In 19th minute it's 50% full, Which is double of 25% which was the capacity of jar in 18th minute

Hence answer is D

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A scientist placed ten bacteria cells in a glass jar. Every minute, th 10 Jul 2020, 06:31
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Bunuel
A scientist placed ten bacteria cells in a glass jar. Every minute, the bacteria double in volume. After 20 minutes, the bacteria completely filled the glass jar. How many minutes did it take for the jar to be 25% full?

A. 4
B. 5
C. 10
D. 18
E. 19
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EVERY MINUTE , THE BACTERIA DOUBLE IN VOLUME

This means at 19th minute the Bacteria = 50%
And at 18th minute the bacteria = 25%
ANS= D
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A scientist placed ten bacteria cells in a glass jar. Every minute, th 27 Jul 2024, 06:48
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