It took me 4 days to read an entire book. I read 1/2 of the total on the first day, 1/4 of the total on the second day, 1/6 of the total on the third day, and 20 pages on the fourth day. Find the total number of pages of this book.
20 1 1/2 1/4 [OP_ADD] 1/6 [OP_ADD] [OP_SUB] [OP_DIV]
var_a = 20
var_b = 1
var_c = 0.5
var_d = 0.25
var_e = var_c + var_d
var_f = 0.16666666666666666
var_g = var_e + var_f
var_h = var_b - var_g
var_i = var_a / var_h
print(int(eval('{:.2f}'.format(round(var_i+1e-10,2)))))