The percent of increase in premium costs from age 70 to age 80 is 337.77%.
What information do we have?
Amount paid in 70's age = $79.79
Amount paid in 80's age = $349.30
Extra amount paid in 80's age = $349.30 - $79.79
Extra amount paid in 80's age = $269.51
Percentage increase = [269.51 / 79.79]100
Percentage increase = [3.377]100
Percentage increase = 337.77% (Approx.)
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