Final answer:
Pae Stri has at least $15 and each sweet costs $2.50. After buying a $5 milkshake, Pae Stri can spend the remaining money on sweets, resulting in an inequality of 2.50s + 5 ≤ 15. After solving, Pae Stri can buy at most 4 sweets.
Step-by-step explanation:
The student, Pae Stri, has at least $15 to spend at the Sweet Shop. To determine how many sweets Pae Stri can buy after purchasing a milkshake, we must first subtract the cost of the milkshake from the total amount of money available. Each sweet costs $2.50, and Pae Stri buys a milkshake for $5, so we set up the following inequality:
2.50s + 5 ≤ 15
Where s represents the number of sweets. We subtract 5 from both sides of the inequality to find out how much money is left for sweets:
2.50s ≤ 10
Dividing both sides by 2.50 gives us:
s ≤ 4
Therefore, Pae Stri can buy at most 4 sweets from the Sweet Shop. This inequality represents the maximum number of sweets that could be bought with at least $15 while also purchasing a $5 milkshake.