To buy 14 balloons, Harry should buy one pack of 10, and 14 - 10 = <<14-10=4>>4 separate balloons.
The price of 4 balloons is 4 * 0.5 = $<<4*0.5=2>>2.
In total, the pack and separate balloons would cost Harry in total 3 + 2 = $<<3+2=5>>5.
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