Question

A train travels 53 kilometers in 4 hours, and then 99 kilometers in 4 hours. What is its average speed?

Answer 1

53 kilometers in 4 hours.

then

99 kilometers in 4 hours again.

it travelled a total of 53 + 99 kilometers, and it did it in 4+4 hours, so on average, it travelled at
`\bf \cfrac{53+99}{4+4}\implies \cfrac{152}{8}\implies 19~(km s)/(hr)`