So (pineapple+apple)+(apple+pear)+(pineapple+pear) = (pineapple+apple+pear) ×2=8+5+9=22 (kg),
Pineapple+apple+pear =22÷2= 1 1 kg,
Pear = 1 1-8=3 (kg),
Pineapple = 1 1-5=6 (kg),
Apple = 1 1-9=2 (kg).