According to the meaning of the question:

Solution: 1≤x≤3,

And x is an integer,

The value of ∴x is 1, 2,3.

When x= 1, the total amount of notebooks purchased is 6× 1+5×4=26 (yuan);

When x=2, the total amount of notebooks purchased is 6×2+5×3=27 (yuan);

When x=3, the total amount of notebooks purchased is 6×3+5×2=28 (yuan).

You should buy 1 large notebook and 4 small notebooks, which will save the most money.

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