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Maths problem

Write in standard form:

1/2 × 5-²

Please explain (the -² is a negative power)

So 5 to the power of -2 is 1/25 then times a half is 1/50 because you can just times fractions across and then 1/50 is 0.02 (assuming you can use a calculator) then 10 x 2 to the power -3

Reply 2

Black Reaper

Guys thanks for all the input but I'd appreciate it if someone could THOUROUGHLY explain (not just what, but also why). Cheebacca seems to be on the right track. Also make it easy to understand (avoid using too many words).

Reply 3

Luiz_Venon

- negative power imply that the numerator and denominator will swap their place.

For example; 2^-3 means 1/2^3. This is because 2 can be written as 2/1, by include the negative power on 2, their numerator and denominator swapped place to 1/2.

Then you just carry out the normal calculation. 2^3 is 8, so the answer to my example is 1/8.

Another example is (3/4)^-2 =(4/3)^2 Once again you swap the position of the denominator and the numerator, then carry out the normal calculation. (4)^2/(3)^2 =16/9

Hope this help.