Income Tax Computation

Hi,

There is a question in Income Tax computation as “Thomas earned £160,000 trading profit in 2023/24 In the tax year he paid £6,400 to charity under the
gift aid scheme.
Calculate Thomas’s income tax liability for 2023/24. ”

In the solution provided at the end, I could in income tax calculation as

(W2) 45,700 @ 20% = 9,140
(W3) 112,300 @ 40% = 44,920
2,000 @ 45% = 900
160,000
Income Tax Liability 54,960

In (W2) Gross gift aid extends both rate bands:
BRB: 37,700 + (6,400 × 100/80) = 45,700
HRB: 125,140 + (6,400 × 100/80) = 133,140

(W3) 133,140 – 45,700 = 87,440

Could you please explain how 114300 is splitted into 112300 and 2000 for tax calculations with suitable calculations and tax liability is 54960 ? while I got it as 54860 by doing 20% of 45700 + 40% of 114300

WHICH IS THE CORRECT ANSWER AND HOW TO RESOLVE THE INCOME FOR HIGHER RATE AND ADDITIONAL RATE IN EXAM AS WELL ?