4yle warts to buy a hat for \( \$ 5.75 \), a T-shirt for \( \$ 7.65 \), and a keychain for \( \$ 3.15 \). He has \( \$ 16 \). Does he have encugh money? Use estimation only to decide. Explain why you are confident in your estimate.

To estimate the total cost, we can round the prices to the nearest whole number: the hat is about \( \$6 \), the T-shirt is about \( \$8 \), and the keychain is about \( \$3 \). Adding these rounded amounts gives us \( \$6 + \$8 + \$3 = \$17 \). Since \( \$17 \) is greater than \( \$16 \), we can confidently say he does not have enough money. Using estimation helps us quickly gauge whether he can make the purchases without getting bogged down in exact calculations. Rounding to whole numbers simplifies the math and speeds up decision-making!