Higher November 2022 Unit 1 Q18

18. Ffion has some blue cards and some yellow cards.
She takes 7 of the blue cards and 3 of the yellow cards and puts them in a box.

Ffion removes one card from the box at random and replaces it with two cards of the other colour.

Then she removes a second card from the box at random.

Calculate the probability that the two cards that Ffion removed are of different colours. [4]