We will use the ratio method to solve the question
∵ 50 kg contains 2 x 10^2 grams of sodium chloride
∵ We need to find the amount of sodium chloride in 1.8 x 10^3 people
who weigh 50 kg
At first, we must find the weight of 1.8 x 10^3 people
Now we will use the ratio method
→ kg: gm
→ 50. : 2 x 10^2
→ 9 x 10^4 : m
→ By using cross multiplication
Divide both sides by 50 to find m
The answer is A