Question

Help i dunno the answer to it :

Answer 1

5 miles per hour

Explanation:

Let the speed of Kelly is
`v_1` miles per hour and speed of Raul is v₂ miles per hour.

Since, speed =
`\frac{\text{Distance}}{\text{Time}}`

Kelly took 135 minutes to cover 90 miles from New York to Philadelphia.

∵ 1 minute =
`(1)/(60)` hours

∴ 135 minutes =
`(135)/(60)` =
`(9)/(4)` hours

v₁ =
`(90)/((9)/(4))`

=
`90* (4)/(9)`

= 40 miles per hour

Raul took 153 minutes to cover the same distance as Kelly,

∵ 1 minute =
`(1)/(60)` hours

∴ 153 minutes =
`(153)/(60)` =
`(51)/(20)` hours

v₂ =
`(90)/((51)/(20))`

`=90* (20)/(51)`

= 35.29

≈ 35.3 miles per hours

v₁ - v₂ = 40 - 35.3

= 4.7

≈ 5.0 miles per hours

Therefore, Kelly is 5 miles per hours faster than Raul.