Quicker Maths

Age Puzzle
If you are 12 years or over:
Write down your age.
Reverse the figures.
So, if your age is 13, reversing the figures gives 31.

There are two consecutive natural numbers whose product is equal to the product of three consecutive natural numbers for example (x + 1) = (y + 1) (y + 2).

A farmer built a fence around his 17 cows, in a square shaped region. He used 27 fence poles on each side of the square.

and counted seven hours per day, how long would it take you to count to a Billion?

TWO HUNDRED EIGHTYSIX DECILLION, FOUR HUNDRED FORTY FIVE NONILLION, THREE HUNDRED AND FIVE OCTILLION, ONE HUNDRED FORTY SIX SEPTILLION, THIRTY NINE SEXTILLION, ONE HUNDRED FORTY QUINTILLION, FORTY SIX QUADRILLION, NINE HUNDRED SIXTY TRILLION, SIX HUNDRED SEVENTY EIGHT BILLION, FIVE HUNDRED EIGHTYTWO MILLION, TWO HUNDRED FIFTY SIX THOUSAND AND THREE. Can you write this as a numeral?

. Any how she scored 85.
Her score was calculated by subtracting two times the number of wrong answers from the number of correct answers.
Can you tell how many problems she solved correctly?

And there were 4 enclosures. I noticed that in each enclosure there were an odd number of chickens.
Can you tell how many there were in each enclosure?

name of the exchange. How many such arrangements of 3 letters is it possible to devise from the 26 letters of the alphabet?