One pack of chips is 75/100 * 4 = $<<75/100*4=3>>3 more expensive than a pack of pretzels.
That means one pack of chips costs 4 + 3 = $<<4+3=7>>7
So Maciek paid 4 * 2 = $<<4*2=8>>8 for the pretzels
He also paid 7 * 2 = $<<7*2=14>>14 for the chips.
In total Maciek paid 8 + 14 = $<<8+14=22>>22 for his purchases.
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