Question

((((((((((((828,829,830,831)))))))))))))))

Answer 1

=1/2*4/3=2/3
=5/12*3/2=5/8
=4/9*3/2=2/3
=8/15*5/4=2/3
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=5/3*2/5=2/3
=12/1*5/6=10
=15/4*4/5=3
=45/4*2/9=5/2=2 1/2
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=5/12*2/5=3/4
=1/4*2/1=1/2
=7/4*8/21=2/3
=1/3*9/12=3/2=1 1/2
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=3/1*2/1=6
=3/4*2/3=1/2
=11/12*6/11=1/2
=25/3*9/5=15

Answer 2

спасибо!