Respuesta :

We are given that a plane covers a distance of 346 miles in 2 1/4 hours. And we are asked to determine the ratio between distance and time. To do that we will divide the total distance over the amount of time, like this:

[tex]r=\frac{346\text{miles}}{2\frac{1}{4}hour}[/tex]

Now, the time is expressed as a mixed fraction. We can rewrite it as a fraction using the following relationship:

[tex]a\frac{b}{c}=a+\frac{b}{c}[/tex]

Applying the relationship we get:

[tex]\frac{346\text{miles}}{2\frac{1}{4}hour}=\frac{346\text{miles}}{(2+\frac{1}{4})hour}[/tex]

Now, we add the fractions:

[tex]\frac{346\text{miles}}{(2+\frac{1}{4})hour}=\frac{346\text{miles}}{\frac{9}{4}\text{hour}}[/tex]

Simplifying we get:

[tex]\frac{346\text{miles}}{\frac{9}{4}\text{hour}}=\frac{4(346\text{miles)}}{9\text{hour}}=\frac{1384miles}{9hour}[/tex]

Now, solving the operation we get the unit rate:

[tex]\frac{1384miles}{9hour}=153.\bar{7}mph[/tex]

Therefore, the unit rate is 157.7 mph.