Speed distance time?

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Answer 1 · 2018-02-17T12:24:16

If they start moving towards each other simultaneously, they will meet after $1$ hour.

If they meet at a distance $x$ from the truck side,

Distance covered by truck will be :

Distance = $x$ = speed x time = $145/2.5 xx t$

$=> x = 58t$ ------(1)

Distance covered by car will be :

distance = $145-x$ = 1.5 times speed of truck x time=

$145-x$ = $1.5 xx 145/2.5 xx t$

$=> -x = (145 xx1.5)/2.5 xx t - 145$

$=>-x = 87 t -145$

$=>x = 145 -87t$ ----(2)

equating (1) and(2):

$58 xx t = 145- 87 t$

$87t +58t = 145$

$=> 145 t =145$

$=> t =1$ hour.

Answer 2 · 2018-02-17T12:28:23

One hour.

Using the fact that $d=rt$ , we first solve for the speed of the truck.

$145=2.5r$
$58=r$

The rate of the truck is 58 miles per hour.

Since the car is 1.5 times faster than the truck, the speed of the truck is $1.5×58$ or $87$ miles per hour.

Now, if the truck and the car are coming towards each other, then it is the same as combining their speed.

Therefore, $145=(58+87)t$

$145=145t$
$t=1$

It takes one hour.