Question

54 kilometers in 4 hours = 81 kilometers in __ hours

Answer 1

6 hr

Explanation:

If 54 km --> 4 hr then,

81 km --> ? hr

You can make a rule of three:

? hr = (81*4)/54

? hr = 6

So 81 km in 6 hours

Answer 2

6 hours

Explanation:

create a proportion:

54 km/4 hrs equals 81km/? hours

`(54)/(4)` =
`(81)/(?)`

solve a proportion by cross-multiplying:

54? = 324

? = 324/54

? = 6