You can use zip and a list comprehension:
pricelist=[373, 381, 398, 402, 404, 457, 535, 550, 566]
pricelist2=[97, 0, 98, 98, 98, 97, 99, 97, 98]
out = [a+b/100 for a,b in zip(pricelist, pricelist2)]
output:
[373.97, 381.0, 398.98, 402.98, 404.98, 457.97, 535.99, 550.97, 566.98]
NB. as pointed out by @OlvinRoght if you plan to use the representation of the output number, better round to avoid floating point precision issues (for example 6+94/100 would give 6.9399999999999995)
out = [round(a+b/100, 2) for a,b in zip(pricelist, pricelist2)]
numpy
You might also be interested in using a specialized library. numpy can handle arrays/vectors very efficiently:
import numpy as np
a1 = np.array(pricelist)
a2 = np.array(pricelist2)
out = a1+a2/100
output:
array([373.97, 381. , 398.98, 402.98, 404.98, 457.97, 535.99, 550.97,
566.98])