a) To solve the equation x - 3.02 = 0.8 ÷ 2.5, we can follow these steps:

Step 1: Simplify the right side of the equation.
0.8 ÷ 2.5 = 0.32

Step 2: Rewrite the equation with the simplified value.
x - 3.02 = 0.32

Step 3: Add 3.02 to both sides of the equation to isolate x.
x - 3.02 + 3.02 = 0.32 + 3.02
x = 3.34

Therefore, the solution to the equation is x = 3.34.

b) To solve the equation 1.2 ÷ x = 1.7 (with a remainder of 0.01), we can follow these steps:

Step 1: Subtract the remainder from 1.7.
1.7 - 0.01 = 1.69

Step 2: Rewrite the equation with the simplified value.
1.2 ÷ x = 1.69

Step 3: Multiply both sides of the equation by x to isolate x.
(1.2 ÷ x) * x = 1.69 * x
1.2 = 1.69x

Step 4: Divide both sides of the equation by 1.69 to solve for x.
1.2 ÷ 1.69 = (1.69x) ÷ 1.69
0.7100591716 = x

Therefore, the solution to the equation is x = 0.7100591716.