I’m not a tutor but please delete if my answer is not allowed…interested to know the actual answer though (if i have not answered it correctly below), i have not yet taken the mocks.
This question looks like a diminution in value one where you look at what the position of the donor is as a result of the gift.
So in this case, Marwa owned 8,000 shares which equals to 80% of the ordinary shares. Therefore:
What Marwa did have = 8,000 x £8 = £64,000
Marwa gifted 6,500 which leaves her with 1,500 shares which is 15% of the total holdings. Therefore:
What Marwa now has = 1,500 x £3 = £4,500
Therefore the diminution in value/transfer value of the gift is £59,500 (64,000 – 4,500)
