Fiona bought a coat for $62 in a state that charges 2.9% sales tax. Sydni bought the same coat for the same price, but in a state that charges 7.25% sales tax.
How much more did Sydni pay for the coat than Fiona?
First we need to calculate the sales tax on the coat for both Fiona and Sydni.
For Fiona, the sales tax is 2.9% of $62 = 0.029 * $62 = $<<2.9*.01*62=1.798>>1.798.
For Sydni, the sales tax is 7.25% of $62 = 0.0725 * $62 = $<<7.25*.01*62=4.505>>4.505.
Therefore, Sydni paid $4.505 - $1.798 = $<<4.505-1.798=2.707>>2.707 more than Fiona for the same coat. Answer: \boxed{2.707}.