Solution 1: Assume that the total book price is X yuan. According to the meaning of the title and the idea of book price, then: X= the money actually spent by Xiao Wang+12.

Namely: X=X*80%+20 (card purchase)+12.

0.2X= 12+20

X= 160 (yuan)

Actual expenditure:160-12 =148 (yuan)

Option 2: let Xiao Wang spend m yuan, and the book price =M+ 12.

According to the actual composition of money, then:

M=20 (card purchase)+book price *80%

So: 20 (card purchase)+(m+12) * 80% = m.

0.2M=29.6

M= 148 (yuan)

Book price =148+12 =160 (yuan)

A: Xiao Wang spent 148 yuan, and the total price of the book was 160 yuan.

Inspection: Xiao Wang's consumption+12=20 (card purchase)+160 * 80%+12 =160.