While hiking, Yunsu drank 7/15 of the water on the first day, 5/8 of the remaining water on the second day, and 2/3 of the rest on the third day. If the amount of remaining water is 2.6 liters (L), what is the amount of water Yunsu had at the beginning?
2.6 1 7/15 [OP_SUB] 1 5/8 [OP_SUB] [OP_MUL] 1 2/3 [OP_SUB] [OP_MUL] [OP_DIV]
var_a = 2.6
var_b = 1
var_c = 0.4666666666666667
var_d = var_b - var_c
var_e = 1
var_f = 0.625
var_g = var_e - var_f
var_h = var_d * var_g
var_i = 1
var_j = 0.6666666666666666
var_k = var_i - var_j
var_l = var_h * var_k
var_m = var_a / var_l
print(int(eval('{:.2f}'.format(round(var_m+1e-10,2)))))