In the first store, each apple costs $3/6 = $<<3/6=0.5>>0.5.
In the second store, each apple costs $4/10 = $<<4/10=0.4>>0.4.
So, you can save $0.5 - $0.4 = $0.1 on each apple from buying $4 for 10 apples than from $3 for 6 apples.
In cents, this is equal to $0.1 x 100 = <<0.1*100=10>>10.
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