Hola:
Este post se titula: "Choo-choo Trains":

Two trains head towards each other on a collision
course along the same track.
Uno sale de la estacion oeste a las 8 am. a velocidad
de 80 mph. Otro sale de la estacion este a las 9 am. con

velocidad de 100 mph. Si hay una distancia de 440 millas

entre las dos estaciones, a que hora van a colisionar
los dos trenes?

_____________________________________

trivia: "Aquellos ojos"
Una niña de cinco años se acerca
a su abuela y le dice:
---Abuelita, puedes cerrarte los ojos?
Abuela: "Por qué, hija? Why do you want
me to close my eyes? "

Niña: "Acabo de oir a Papá dile a Mamá:
When she closes her eyes
we'll be rich!"

'ta luego.
Hice este tipo de problemas arithmaical cuando yo estaba en la escuelaEmotion: stick out tongue
JhumkaHice este tipo de problemas arithmaical cuando yo estaba en la escuela Emotion: stick out tongue
Glad to have you on my post, Jhumka.

Entonces, ¿puedes explicarnos la respuesta? (sin el uso de ningun
equacion, si puedes).
Pff, demasiado dificil para mi, no sé dónde meter las horas.
Two trains head towards each other on a collision
course along the same track.
Uno sale de la estacion oeste a las 8 am. a velocidad
de 80 mph. Otro sale de la estacion este a las 9 am. con
velocidad de 100 mph. Si hay una distancia de 440 millas
entre las dos estaciones, a que hora van a colisionar
los dos trenes?

8.00 (tiempo cero): 440 millas.
9.00 . 360 millas.
10.00 . 180 millas.
11.00: ¡CRASH!
PuccaPff, demasiado dificil para mi, no sé dónde meter las horas. Emotion: tongue tied
Hi, Pucca:

One easy way to figure out number problems like these is by
simple practical reasoning as follows:

1. Distance between stations: 440 miles.
2. First train leaves 8am at 80mph.
3. Second train leaves 9am at speed, 100mph.

Problem: By what time will the two trains collide? Simple arithmetic will tell us that:

a) By 10am: The first train has been travelling for 2 hours at 80 mph, so it must have
covered 160 miles (80 x 2). The second train has been running for 1 hour
(having left the station at 9am.), so it must have covered 100 miles. So the two
trains together have covered a total of 260 miles by 10am (160 + 100). This
means that by 10am the two trains are still 180 miles away from each other
(440 - 260 = 180).
b) By 11am: ( 3 hrs. later) First train has covered 240 miles (80 x 3).
Second train has covered 200 miles (100 x 2). This means that
by 11am the two trains have covered a total of 440 miles !!
So, COLLISION TIME is: 11 a.m.

THE EQUATION IS: Let X be the travel time of both trains to cover 440 miles.

100(X-1) + 80X = 440
a) 100X - 100 + 80X = 440

b) 100X + 80X = 440 + 100

c) 180X = 540

d) X = 540 divided by 180

e) X = 3 (hours)

'ta luego. Next time it will be much easier.[H]M
TitoIndigo8.00 (tiempo cero): 440 millas.
9.00 . 360 millas.
10.00 . 180 millas.
11.00: ¡CRASH![Y]
Hola, Tito:
You and I know what those figures in your
post are all about. But they may be a big puzzle
to most of our forofriends. So, it may not be
a bad idea if they could be accompanied by
a simple, practical explanation as how
those figures are arrived at.

Todos aquellos problemas "aritmeticas" que he
postado son capaces de solucionar por medio de
razonamiento logico sin necesidad de ningun
conocimiento de álgebra. It is never my intention
to test the algebraic knowhow of our foromates.
I myself love to solve number problems by pure
practical sense. After all, math is based on nothing

more than cold logic.

Thanx,Tito. 'ta luego.