Question

two cars leave at the same time from opposite points on a road. One travels at 40km/h and the other at 60km/h. If the distance between the starting points is 300 km, how many hours will it take to meet?​

Answer 1

Respuesta:

NOSE ABLAR INGLES

Explicación paso a paso:

PERDON PLISS

Answer 2

Respuesta:

2 hours and 39 minutes approximately

Explicación paso a paso:

we make a graphical representation of the mobiles A and B

∙ A⟶ ————————— ⟵ ∙ B

∙ A⟶ – x ——— (200000-x) —- ⟵ ∙ B

Va = 30 km / h = 30. (1000) / 3600 = 8.33 m / s

then the distance traveled from A will be:

Vb = 12.5 m / s

Va = x / ta

ta = x / Va

Vb = (200000 -x) / tb

tb = (200000-x) / Vb

But since the mobiles came out simultaneously, then the time from a to the same time from b.

ta = tb

x / Va = (200000-x) / Vb

x / 8.33 = (200000 -x) /12.5

12.5x = 8.33 (200000 -x)

12.5x + 8.33x = 1666000

20.83x = 1666000

x = 1666000 / 20.83

x = 79,980.79 meters = 79.98 Km

Then the distance traveled from A will be:

X = 79.98 Km

And the distance traveled from B will be:

200 -79.98 = 120.02 Km

The time to meet will be:

ta = tb = t

t = 79.98 km / 30 km / h = 2.66 hours = 2 hours and 39 minutes approximately