[讨论] level 1 financial statement DTL 一题

page 203 Q 10

my way is
income tax expense
= tax expense in income statement + delta (DTL - DTA)
＝（50 - 30）x 50% + 10 x 10%
= 11 k

this is same as page 194 example, tax expense + change in previous accumulated (DTL - DTA)

but answer shows different approach, which i don't think is correct,
tax payable + increase in deferred tax
= 5 + (10 - 4) = 11k
why?