Final answer:
A word problem about two friends saving for a concert introduces simultaneous linear equations representing individual and total savings, which are solved to find the number of days each saved.
Step-by-step explanation:
Two friends, Alice and Bob, decide to save money for a concert. Alice saves $2 per day, and Bob saves $3 per day. After a certain number of days, they together saved $110. Let x represent the number of days Alice saves money, and y the number of days Bob saves money. The first equation representing Alice's savings is 2x = y. The second equation representing their total savings is 2x + 3y = 110. Solving these simultaneous linear equations will give us the number of days each person saved to reach the total amount of $110.