Rico thinks of a number between 30 and 40 that is represented by
x
.

This number,
x
, is
3
_
4
of another number, which is represented by
y
.

The number represented by
y
equals
1
_
3
of another number, which is
represented by
z
.

The number represented by
z
is a number from 140 to 151.

The numbers represented by
x
,
y
, and
z
are whole numbers.
(a)
What are the values for
x
,
y
, and
z
?

Respuesta :

caylus
Hello,

x,y,z∈ IN

[tex] x=\frac{3}{4}*y [/tex]
[tex] y=\frac{1}{3}*z [/tex]

[tex]140<z<151\ ==>\ \frac{140}{3}<\frac{z}{3}<\frac{151}{3}[/tex]
[tex]46\leq\ y\ \leq\ 50 ==>\ \frac{46*3}{4}\leq\frac{3y}{4}\leq\frac{50*3}{4}[/tex]
[tex]35\ \leq\ z\ \leq\ 37[/tex]==>
 x∈{35,36,37}
 y∈{47,48,49}
 z∈{141,144,147}

We must go futher:

if x=35 then y=4*35/3=46.666 not good , not whole
if x=36 then y=4*36/3=48 ok
if x=37 then y=37*4/3=49.333.. not good

So there is only one solution (36,48,144) for (x,y,z)

No problem with z for z=3/1*4/3*x=4x ==>whole.