Answer: 9
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Explanation:
The ratio 3:2 scales up to 3x:2x for some positive whole number x.
We have 3x white pieces, 2x black pieces, and 3x+2x = 5x pieces total. Set this equal to the 15 mentioned and solve for x.
5x = 15
5x/5 = 15/5
x = 3
Therefore, there are 3x = 3*3 = 9 white pieces and 2x = 2*3 = 6 black pieces, which gives 9+6 = 15 total. The ratio 9:6 reduces to 3:2 after dividing both parts by the GCF 3.
