The answer should be 2.2, or as a fraction from 2 and 1/5
as 2 and 3/4 can be changed to 2.75 and 4/5 can be changed to 0.8
Well, their speeds are (

is Jack's speed, and

is Richard's.

They, together, can paint 12 houses in 35 days. To get a single house, we only have to calculate

which is very close to 3 (a bit below)
Answer:
I have made it in above pic
Constantinople has a total of 14 letters of which 9 are consonants
P(picking a consonant) = 9/14
P(2 letters are consonants with replacement) = 9/14 * 9/14 = 81/196