Michelle uses 5 x 2 = <<5*2=10>>10 red beads.
She uses 5 + 10 = <<5+10=15>>15 white beads.
So she uses a total of 5 + 10 + 15 = <<5+10+15=30>>30 blue, red, and white beads.
Therefore, she uses 40 - 30 = <<40-30=10>>10 silver beads.
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