Squares, roots and powers
Squares, roots and powers

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Squares, roots and powers

2.1.1 Try some yourself

Activity 15

The size of a population of micro-organisms doubles every hour. If there are two of these creatures to start with, how many will there be after five hours?

Answer

After one hour there are 2 × 2 = 4 micro-organisms.

After two hours there are 2 × 4 = 8, or 2 × 2 × 2 = 23.

After five hours there are 2 × 32 = 64, or 2 × 2 × 2 × 2 × 2 × 2 = 26.

So there will be 26 = 64 after five hours.

(Note: if you gave 32 as your answer, maybe you forgot that there were 2 organisms to start with.)

MU120_4M4

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