Let x be the original price.
Christa buys at 45% of the price
⇒ 0.45x
The price increase by 150%
⇒1.5 x 0.45x + 0.45x
⇒1.125x
1.125x = 112.5% of x
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Answer: The new sales price is 112.5% of the original price.
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