Given :
Father drove 176 km in 7 hours.
For the first 92 km he spent for 4 hours.
To Find :
His average speed for the remaining journey .
Solution :
[tex]v_{avg}=\dfrac{u_1+u_2}{2}\\\\v_{avg}=\dfrac{u_1}{2}+\dfrac{u_2}{2}\\\\\dfrac{176}{7}=\dfrac{92}{4\times 2}+\dfrac{u_2}{2}\\\\\dfrac{u_2}{2}=\dfrac{176}{7}-\dfrac{92}{8}\\\\u_2=13.64\times 2 \ km/h\\\\u_2=27.28\ km/h[/tex]
Therefore , his average speed for the remaining journey is 27.28 km/h .
Hence , this is the required solution .
