Question

Question #20130

Answer 1

See the answer below....

Explanation:

Let,she takes `color(red)(t` hours to reach his destination and the distance of his destination is `color(red)(d" km"`.

1)To reach the destination with a velocity of `color(green)(25" km"//"h"`,she takes `color(violet)(d/25` h

• `|ul(bar(color(blue)(t-1=d/25)))|" ".........(1)`

2)To reach the destination with a velocity of `color(green)(30" km"//"h"`,she takes `color(violet)(d/30` h

• `|bar(ulcolor(blue)(t-15=d/30))|" ".........(2)`

From both equation,we get `" "color(red)(25t-25=30t-450)=>color(red)(5t=425)=>color(red)(t=85`

Hence,the distance of her destination is `color(red)(85xx25-25)=color(red)(2100" km"`

To overcome the distance with a velocity of `color(red)(20 "km"//"h"` ,she takes `color(blue)(2100/20=105" h"`

`ul("conclusion:-")" "`She takes `color(green)(105-85)=color(red)(20` hours more.

Hope it helps...
Thank you...