If, in a certain code language: 'black colour Pen' is coded as 356, 'white colour flower' is coded as 587, 'red colour Pen' is coded as 345, then how 'black' and 'red' shall be coded in that code language, respectively ?

'black' is coded 6 and 'red' is coded 4.

'colour' appears in all three groups, and 5 is the digit common to all, so colour = 5.

'colour Pen' appears in 356 and 345 ; their shared digits are 5 and 3, so Pen = 3.

In 356 the leftover digit is 6, giving black = 6.

In 345 the leftover digit is 4, giving red = 4.