If a woman weighs 125 lb, her mass expressed in kilograms is x kg, where x is

Weight of the women in pounds = 125 lb

1 kg is heavier than 1 pound and 1 Kilogram is same as 2.20462 pounds.

So 125 lb gives 125 / 2.20462 kilo grams = 56.699 kg and the value is less than 125.

The first thing you should know to solve this problem is the conversion of pounds to kilograms:

1lb = 0.45 Kg

We can solve this problem by a simple rule of three

1lb - - - > 0.45Kg

125lb - - - > x

Clearing x we have:

x = ((125) / (1)) * (0.45) = 56.25 Kg.

Answer

her mass expressed in kilograms is 56.25 Kg.