Total runs scored by three batsmen x, y and z are 1584. Ratio of runs scored by x and y is 4 : 3 and y and z is 5 : 3. How many runs are scored by x?

Total runs scored = 1584

Ratio of runs scored by = $$\frac{x}{y}=\frac{4}{3}$$ ------------(i)

and $$\frac{y}{z}=\frac{5}{3}$$ ----------------(ii)

Multiplying equation (i) by '5' and equation (ii) by '3' to equate value of $$y$$, we get :

=> $$\frac{x}{y}=\frac{20}{15}$$ and $$\frac{y}{z}=\frac{15}{9}$$

=> $$x:y:z=20:15:9$$

Let runs scored by $$x,y$$ and $$z$$ respectively be = $$20k,15k,9k$$

=> Total runs = $$20k+15k+9k=44k=1584$$

=> $$k=\frac{1584}{44}=36$$

$$\therefore$$ Runs scored by $$x=20\times36=720$$

=> Ans - (D)