If a tour costs the tour operator $1,500 per person and the operator has a markup of 15 percent, how much would a pair of customers pay for tours? $3,450

$300

$3,300

$3,000

 Current number of butterflies in the park = 20 thousand.

 Rate of increase of butterfly population = 4% = 0.04

The population of butterfly after 1 year = 20+0.04*20 = 20*1.04

The population of butterfly after 2 years =  20*1.04 + 20*1.04*0.04 = 20*1.04*1.04

 The population of butterfly after 3 years =  20*1.04*1.04 + 20*1.04*1.04*0.04 = 20*1.04*1.04*1.04

So, population of butterfly after n years = 20*(1.04*1.04*1.04* n times)