SSC MTS 2022 PYQ — Question 65

The correct answer is option 4 i.e. 60

Average of D₁ and D_{2 = $\left ( \frac{D_{1}+D_{2}}{2} \right )$}

$40=\left ( \frac{D_{1}+D_{2}}{2} \right )$  

D₁ + D₂ = 80

Average of D₂ and D_{3 = $\left ( \frac{D_{2}+D_{3}}{2} \right )$}

$45=\left ( \frac{D_{2}+D_{3}}{2} \right )$      

D₂ + D₃ = 90

Average of D₁ and D_{3 = $\left ( \frac{D_{1}+D_{3}}{2} \right )$}

$55=\left ( \frac{D_{1}+D_{3}}{2} \right )$

D₁ + D₃ = 110      

So,

D₁ + D₂ + D₂ + D₃ + D₁ + D₃ = 80 + 90 + 110

2D₁ + 2D₂ + 2D₃ = 280

2(D₁ + D₂ + D₃) = 280

D₁ + D₂ + D₃ = 140

Now,

80 + D₃ = 140

D₃ = 140 - 80 = 60