How much should you weight if your height is 169 cm?

170cm = 5ft 10inch

1 pound = 0.453 kilogram
1 inch = 2.540 centimeters

The Below describes pounds. Age does not factor in below, although I think it does matter, as hormones change. Sources below.

Male:
Small Frame: 144 - 154
Medium Frame: 151 - 163
Large Frame: 158 - 180

Female:
Small Frame: 132 - 145
Medium Frame: 142 - 156
Large Frame: 152 - 173

http://www.dietbites.com/article1023.html
http:/www.healthchecksystems.com/heightweightchart.htm