the table say that at 20 degree celcius 88.0g of NANO3 will remain dissolved in
100 gm of H2O
so at 20 degree celcius 80.0g of H20 will dissolve
(88.0g)x(80g/100g)=70.4g of NANO3
so at 20 degree celcius
86.3g-70.4g= 15.9 gram of NANO3 will come out of solution.