Correct Answer - Option 2 : 9 : 14
Given:
Female rat in particular experiment = 60%
Male rats in particular experiment = 40%
Female rats died in experiment = 70%
Male rats died in experiment = 30%
Calculation:
Let the number of rats be x
The number of female rats = 60% of x = 0.6x
Number of male rats = 40% of x = 0.4x
Let the number of rats that died be y
The number of female rats died = 70% of y = 0.7y
Number of male rats died = 30% of y = 0.3y
Death rate of male rats = \(\frac{0.3y}{0.4x}\) = \(\frac{3y}{4x}\) ----(I)
Death rate of female rats = \(\frac{0.7y}{0.6x}\) = \(\frac{7y}{6x}\) ----(II)
Equating (I) and (II)
⇒ \(\frac{3y}{4x}\) = \(\frac{7y}{6x}\) = 18xy : 28xy
∴ The ratio of the death rate of male to female rats is 9 : 14