algebra: find percentage increase

[pboland]

In the famous clinical trial of the estrogen-progestrin drug Prempro, there were 38 cases of breast cancer per 10,000 women on the drug. There were 30 cases of breast cancer per 10,000 women on placebo. Find the percentage increase in breast cancer risk for women taking the hormone.
38 - 30 / 30 (100%) =
.267 (100%)=
26.67%

 

[tkhunny]

38 - 30 / 30 (100%) =
.267 (100%)=
26.67%

Sorry.

38 - 30 / 30 (100%) =
38 - 1 (100%) =
38 - (100%) =
38 - 1 =
37 and what does that even mean?

I'm just picking on your notation. Please be more careful and much more clear.

(38 - 30) / 30 (100%)

Parentheses are beautiful things.

 

[pboland]

(38-30) / 30 (100%)=
(.267) (100%) = 26.67
27%
thank you for your help.