If $A: B = 3: 4$,$B: C = 4: 5$,and $C: D = 5: 6$,then $A: D$ will be

If $P: Q = 8: 15$,$Q: R = 5: 8$,and $R: S = 4: 5$,then $P: S$ is equal to

If $A: B = 2: 3$,$B: C = 4: 5$,and $C: D = 6: 7$,then $A: B: C: D$ is

The respective ratio between the speeds of a car,a jeep,and a tractor is $3:5:2$. The speed of the jeep is $250\%$ of the speed of the tractor,which covers $360 \text{ km}$ in $12 \text{ hours}$. What is the average speed of the car and the jeep together in $\text{km/h}$?

The ratio between the present ages of Indira and Lizzy is $3:8$,respectively. After $8 \text{ yr}$,Indira's age will be $20 \text{ yr}$. What was Lizzy's age $5 \text{ yr}$ ago (in $\text{yr}$)?

If $(x+y):(x-y)=11:1$,find the value of $\frac{(5x+3y)}{(x-2y)}$.