Answer:
1
2
3
,
3
Step-by-step explanation:
Let's call the digits of the number ab a and b. Then the information in the question can be expressed as
a+b=12 => b=12-a
a*10+b + 54 = b*10+a => 9a + 54 = 9b
9a + 54 = 9(12-a) => 18a = 54 => a=3
b=12-a; b=9
39 swapped gives 93, 39+54=93
Given:
x, y and z are integers.
To prove:
If 
is even, then at least one of x, y or z is even.
Solution:
We know that,
Product of two odd integers is always odd. ...(i)
Difference of two odd integers is always even. ...(ii)
Sum of an even integer and an odd integer is odd. ...(iii)
Let as assume x, y and z all are odd, then is even.
is always odd. [Using (i)]
is always odd. [Using (i)]
is always even. [Using (ii)]
is always odd. [Using (iii)]
is always odd.
So, out assumption is incorrect.
Thus, at least one of x, y or z is even.
Hence proved.
10 : 40
divide each side by 40
0.25 : 1
It grows 1/4th of a foot in one day.
