Question

How do you express `0.00000054` in scientific notation?

Answer 1

We need to write `axx10^b`, where `a` has just one non-zero digit before the decimal point.

Explanation:

To change the given number to `5.4`, we need to move the d.p. 7 places to the right. This means that the 10-power is negative and equal to -7.

`=5.4xx10^(-7)`

Answer 2

`5.4xx10^(-7)`

Explanation:

Scientific notation is composed of a "mantissa" and an "exponent".

The mantissa is a decimal number with one non-zero digit to the left of the decimal point (except, of course, if the number is exactly zero).

The "exponent" is `10` to some power, where the power indicates how many decimal positions the decimal point in the mantissa needs to be moved (to the right if the exponent is positive; to the left if the exponent is negative) to form the actual value of the number.

The mantissa for `0.00000054` is `5.4`
and
it is necessary to move the decimal point `7` positions to the left from `5.4` to get the actual value; there fore the "exponent" portion is `10^(-7)`