Question 518233
or those people with highly sensitive skin, an ultra-violet, or UV, rating of 6 will cause sunburn after 10 min.
 Given that the number of minutes it takes to burn t varies inversely as the UV rating u, how long will it take a highly sensitive person to burn on a day with a UV rating of 4?
:
let t = time to burn on a 4UV day
;
Varies inversely so we can write it
{{{6/4}}} = {{{t/10}}}
Cross multiply
4t = 60
t = {{{60/4}}}
t = 15 min