Problem
Add Liam 2, Noah 4, Owen 5, Jacob 3 to get 14 in total.
Adding every student's circle count builds the team total — on the graph each student is a part of the whole, and adding all the parts gives exactly the whole.
Identify Subproblems2.MD.D.10Tables And GraphsSince Liam's team has 2 more, Mia's team total is 12.
'2 more' means adding 2 to Mia's total gives Liam's total, so subtracting 2 back off Liam's total undoes that and gives Mia's total.
Identify Subproblems3.MD.B.3Take Sophia 4, Ethan 2, Emma 3 from Mia's total 12 to get Jordan's 3.
Mia's team total is all four students' counts added together, so subtracting the three known students (Sophia, Ethan, Emma) undoes that addition — the amount left is exactly the one count never removed, Jordan's.
Identify Subproblems2.MD.D.10Subtracting the three known Mia-team students from Mia's team total leaves the number of questions Jordan answered correctly.
A team total is every student's correct answers added together, so the four students' counts are the parts that build up that whole.
The team is exactly its four members with nobody left out and nobody counted twice, so their separate counts add back to the team total.
Taking the three counts we know back out of the total reverses the adding, so the amount still left is the one count that was added but never removed — Jordan's.
Subtraction undoes addition, so removing amounts that were added leaves exactly the amount that was not taken out.
Find one team's total, use the difference to get the other team's total, then subtract the known students to reveal the missing one.