Final answer:
The situation can be represented by the numerical expression (50 × 3) - 25, where Chelsea first triples her $50 bank balance and then subtracts $25 to account for the purchase of a new shirt.
Step-by-step explanation:
To represent the situation where Chelsea tripled her bank balance and then withdrew money to buy a shirt, we can use a numerical expression. Chelsea starts with a bank balance of $50. According to the problem, she triples her bank balance, which means multiplying by 3, and then she withdraws $25 to buy a new shirt.
The numerical expression for this situation is: (50 × 3) - 25.
The first part of the expression (50 × 3) represents the tripling of her initial bank balance. Subtracting 25 from that amount represents the withdrawal made to purchase the shirt. Thus, when we perform the calculations inside the parentheses first and then subtract 25, we will obtain Chelsea's bank balance after these transactions.