Question 1006172
At 2 PM, with 24 hr clock, {{{ x = 14 }}}
{{{ f(x) =-.08*( x-13 )^2 + 9 }}}
{{{ f(14) = -.08*( 14-13 )^2 + 9 }}}
{{{ f(14) = -.08*( 1 )^2 + 9 }}}
{{{ f(14) = 8.92 }}}
UV index is 8.92
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If UV index is {{{ 7 }}},
{{{ f(x) = - .08*( x-13 )^2 + 9 }}}
{{{ 7 = -.08*( x-13 )^2 + 9 }}}
{{{ -.08*( x-13 )^2 = 7 - 9 }}}
{{{ ( x-13 )^2 = (-2)/(-.08) }}}
{{{ ( x-13 )^2 = 1/.04 }}}
{{{ x - 13 = sqrt( 25 ) }}}
{{{ x - 13 = 5 }}}
{{{ x = 18 }}}
This would be 6 PM on the 24 hr clock