Question

Which is the more reasonable measurement of the diameter of a blood cell: 7.4 ⋅ 10−3 mm or 7.4 ⋅ 103 mm? Justify your answer.

Answer 1

I think that it is the first one because it is smaller


hope this helped!!

Answer 2

`7.4* 10^(-3)\ mm`

Explanation:

Actual measurement of diameter of a blood cell is 6 to 8 μm

Let diameter be d

`1\mu m=10^(-6)\ m`

`6* 10^(-6)\ m\leq d\leq 8* 10^(-6)\ m`

Now we check the given measurement between the range.

• 
  `7.4* 10^(-3)\ mm`

Change into meter. As we know 1000 mm = 1 m or 1 mm = 10⁻³ m

`7.4* 10^(-3)* 10^(-3)\ m`

`7.4* 10^(-6)\ m`

• 
  `7.4* 10^(3)\ mm`

`7.4* 10^(3)* 10^(-3)\ m`

`7.4\ m`

So,
`7.4* 10^(-6)\ m` lie between
`6* 10^(-6)\ m\leq d\leq 8* 10^(-6)\ m`

Hence,
`7.4* 10^(-6)\ m` more reasonable measurement of diameter of blood cell because it lies between range of diameter of blood cell.