ok im still needing a little more help with blood types!?

Question

ok this is just an example of a problem that i didnt understand how to set up. it kind of cheezy but my pre ap biology teacher gave it to me and i have no idea what to do. ok it said that 3 babies were mixed up in the hospital. and they have to compare thier blood types with the parents to find out which baby is theirs. the first baby has blood type A, the second baby has blood type O, and the 3rd has blood type AB. then they have a list of 3 parents, 1st parents whose name is Smith w/ blood types AB and A, 2nd parents Jones blood types are B and A,3rd parents are blood type O and AB now you just have to match the parents with the baby. i dont know if you would do a punnett square to determine the baby with the parents or what! help me i dont understand!!! Please!!

Answer 1

Baby 1 = Blood type A (has to get AA or AO from parents)

Baby 2 = Blood type O (has to get OO from parents)

Baby 3 = Blood type AB (has to get AB from parents)

Smiths = Type AB and Type A THIS ANSWER IS THE LAST ONE TO BECOME CLEAR BECAUSE YOU'VE ALREADY SOLVED THE OTHER TWO BABIES.
--- Can't have a Type O baby, so not Baby 2
--- The only baby left is Baby 3. Now you just have to see if that's possible. Baby 3 is Type AB, so you check to see if this baby could get an A from one parent and a B from the other parent. Yep! So the Smiths are Baby 3's parents.

Joneses = Type B and Type A THIS ANSWER IS THE FIRST ONE YOU CAN FIGURE OUT.
--- Only pair that can have a Type O baby because parents can be BO and AO. So they have to be Baby 2's parents.

Others = Type O and Type AB THIS ANSWER IS THE SECOND ONE THAT BECOMES CLEAR.
--- Can't have a Type O baby, so not Baby 2
--- Can't have a Type AB baby because that baby would have to get either the A or the B from the Type O parent, and that's not possible. Must be Baby 1's parents.

Answer 2

Start with the possible combinations of blood types for each parent. Remember each parent has two alleles, that is the Smith parent with the A blood type can either be AA or AO. The other Smith parent is blood type AB, so they will have an A allele and a B allele
So the Smith baby can be: AA, AB, AO, or BO.
Then go to the next pair and work it out by elimination.