=(6/13+1/13)x6/29+6/13x22/29
=6/13x6/29+1/13x6/29+6/13x22/29
=6/13x6/29+6/13x1/29+6/13x22/29
=6/13x(6/29+1/29+22/29)
=6/13x29/29
=6/13x1
=6/13
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