From the grocery store you need to purchase 1/2 lb cheese, 2 lbs sliced ham, 2 loaves of bread, 3 bags of potato chips, and 2 containers of salsa. You have a coupon for $3.00 off if your purchase totals more than $25.00 or 10% off if the total is more than $30.00. The food sales tax is 4%. What is your total purchase?

To calculate the total cost of your grocery purchases, follow these steps:

### Step 1: Calculate the cost of each item.
- **Cheese:**
\[
0.5 \, \text{lb} \times 2.99 \, \text{USD/lb} = 1.495 \, \text{USD} \text{ (rounded to } 1.50 \text{ USD)}
\]

- **Sliced Ham:**
\[
2 \, \text{lbs} \times 4.29 \, \text{USD/lb} = 8.58 \, \text{USD}
\]

- **Bread:**
\[
2 \, \text{loaves} \times 2.49 \, \text{USD/loaf} = 4.98 \, \text{USD}
\]

- **Potato Chips:**
- Cost for 3 bags = 3.00 (2 for $3) + 1.99 (1 bag) = 4.99 USD

- **Salsa:**
\[
2 \, \text{containers} \times 3.39 \, \text{USD/container} = 6.78 \, \text{USD}
\]

### Step 2: Total Cost Before Tax
Sum all the item costs:
\[
1.50 + 8.58 + 4.98 + 4.99 + 6.78 = 26.83 \, \text{USD}
\]

### Step 3: Calculate Sales Tax
Sales tax at 4% on the total:
\[
26.83 \, \text{USD} \times 0.04 = 1.0732 \, \text{USD} \text{ (rounded to } 1.07 \text{ USD)}
\]

### Step 4: Total Cost After Tax
\[
26.83 + 1.07 = 27.90 \, \text{USD}
\]

### Step 5: Apply Coupons
Since the total ($27.90) is more than $25.00, you can use the $3.00 coupon:
\[
27.90 - 3.00 = 24.90 \, \text{USD}
\]

### Summary of Total Purchases:
The total cost of your grocery purchases after tax and the coupon is **$24.90**.