To make one ribbon, you need 4 meters (m) of string. If Jimin bought 105.8 meters (m) of string, make as many ribbons as possible and find the length of the remaining string.
105.8 4 [OP_MOD]
var_a = 105.8
var_b = 4
var_c = var_a % var_b
print('{:.2f}'.format(round(var_c+1e-10,2)))