Solve for r: 0.04r = 52.60.

1. The variable r is multiplied by 0.04, so divide both sides by 0.04. 2. This gives r = 52.60 / 0.04. 3. Dividing by 0.04 is the same as multiplying by 25: 52.60 x 25 = 1,315. 4. So r = 1,315. 5. Check: 0.04 x 1,315 = 52.60, while r = 131.5 comes from dividing by 0.4 instead of 0.04. _Source: OpenStax Elementary Algebra (CC BY 4.0), Ch 2 "Solving Linear Equations and Inequalities", section 2.2 Solve Equations using the Division and Multiplication Properties of Equality_