DAY 23

Comment

As a start, what, for example, is the last number in row 21 ?

Answer

The number in row 21, column 4 is 124.

Readers' methods

Jimmy C, Levenshulme M19:
The numbers in column 4 go up by 6 each time.
The number in column 4 row 1 is 4,
so I want 4 plus 20 lots of 6,
which is 4 plus 120,
which is 124.

Adrian T, Loughborough LE11:
The value of the number X in row m, column n is given by:
X = n + 6(m - 1).
So here, m = 21, n = 4, and therefore
X = 4 + (6 x 20) = 124.

Ben B, Harrow HA2:
For a table with n columns, the formula for the number, x, in row r, column c is
x = [(r - 1) * n] + c.
Therefore in this case
x = [(21 - 1) * 6] + 4
= [20 * 6] + 4
= 120 + 4
= 124.