BPP Pages 272 assocate to subsidiary acquisition

Hi sir
I have a question regarding to calculation of gain on remeasurement

Peace acquired 25% of Miel on 1 january 20X1 for january and a further 35% was acquired on 30 September 20X9

So i calculated gain on remeaurement
FV at date control achieved = 800 ^ 14.5 ^ 60% (20X2.sep 30)
Carrying amount of investment = 2020 + (7800-2800) ^ 25%
= 6960 -2520 = 4440

But the answer was
FV at date control achieved = 800 ^ 14.5 ^ 25 %
Carrying amount of investment = 2020 + (7800-2800) ^ 25%
= 2900-2520 = 380

Im confusing why it is multiplied 25% not the 60% because the date that company got the control is 30 September 20X2 which is 60 % ..

Can you please explain this..?

Many thanks!