Question 887106
Both start at 1.00 pm

let train speed be x mph

Marcial travels by train for 12 minutes= 1/5 hours

distance traveled by Marcial = (1/5) * x = x/5 miles

Then Marcial walks for 1 hour perpendicular to the train.
speed = 3.5 mph
time = 1 hour

distance = 3.5 miles

Chokie rides 1 hour + 12 minutes to reach Marcial.
=6/5 hours
chokie's speed = 10 mph
distance chokie meets Marcial = 6/5 * 10 = 12 miles

So apply Pythagoras theorem

12^2= (x/5)^2+ (3.5)^2

144-12.25 = x^2/25

131.75 =x^2/25

x^2= 3293.75
x=57.4

Train speed = 57.4 mph