23) It takes a bus 6 hours to take a trip. The train takes only 4 hours to make the same trip. The train travels at a rate of speed that is 25 mph more than the speed of the bus. What is the rate of the bus and the rate of

the train? State what x represents, state the equation, and then state the answer.

Rate Time Distance

Bus x 6 бах

Train x-? 2(x+3)

Distance bus travels – Distance train travels

x  = 50 mph        speed of the bus

y  = 75  mph       speed of the train

Step-by-step explanation:

Lt´s call  "x" speed of bus   and  "y" speed of train.

According to the problem statement

6*x  =  4*y                   (1)

y  =  x  + 25                 (2)

We solve for x and y the two equation system

y = ( 6/4)*x

( 6/4)*x  =  x  +  25

6*x = 4*x + 100

2*x  = 100

x  = 50 mph

And

y  =  (6/4)*x

y  = 300/4

y  = 75 mh

i think it's eleven too, don't woosh me here, but according to the "experts" it's 2.

the proof starts from the peano postulates, which define the natural

numbers n. n is the smallest set satisfying these postulates:

  p1.   1 is in n.

  p2.   if x is in n, then its "successor" x' is in n.

  p3.   there is no x such that x' = 1.

  p4.   if x isn't 1, then there is a y in n such that y' = x.

  p5.   if s is a subset of n, 1 is in s, and the implication

      (x in s => x' in s) holds, then s = n.

then you have to define addition recursively:

  def: let a and b be in n. if b = 1, then define a + b = a'

      (using p1 and p2). if b isn't 1, then let c' = b, with c in n

      (using p4), and define a + b = (a + c)'.

then you have to define 2:

  def:   2 = 1'

2 is in n by p1, p2, and the definition of 2.

theorem:   1 + 1 = 2

proof: use the first part of the definition of + with a = b = 1.

      then 1 + 1 = 1' = 2   q.e.d.

note: there is an alternate formulation of the peano postulates which

replaces 1 with 0 in p1, p3, p4, and p5. then you have to change the

definition of addition to this:

  def: let a and b be in n. if b = 0, then define a + b = a.

      if b isn't 0, then let c' = b, with c in n, and define

      a + b = (a + c)'.

you also have to define 1 = 0', and 2 = 1'. then the proof of the

theorem above is a little different:

proof: use the second part of the definition of + first:

      1 + 1 = (1 + 0)'

      now use the first part of the definition of + on the sum in

      parentheses:   1 + 1 = (1)' = 1' = 2   q.e.d.

all you should have to do is insert 1 where the c is, representing that one car is sold.

f(c) = 250c + 500

f(1) = 250(1) + 500

f(1) = 250 + 500

f(1) = 750

he earns $750 for each car sold.

hope this you! have a happy , here's a turkey!