Finance Interest Problems
Interest problems ask you to track how money grows or how debt accumulates over time. You'll work with simple interest (a fixed amount each period) and compound interest (interest earning interest), and the difference between the two is where most of the learning happens. A savings account growing at 4% compounded monthly behaves very differently from one earning 4% simple interest, and these problems teach you to quantify that difference. You'll also encounter loan amortization, comparing investment options, and figuring out how long it takes to double your money. This is one of the most directly practical categories — you'll use these skills every time you evaluate a mortgage, a car loan, or a retirement plan.Write and solve the exponential equation 3^h = 6,561 to find when algae reaches that population.
Bacteria double every 5 minutes. Find when population reaches 16 and 64 cells. Exponential models.
A company gains 10% customers per quarter starting at 1,500. Find total after 100 quarters.
Find annual house appreciation rate (1985–2005), then predict 2010 value. Exponential growth problem.
Find when population density reaches 1 person per square yard using exponential growth. 4.9% annual rate, 4.9M initial population.
Use kinematic equations to find vertical separation when a falling pot has different speeds at two heights.
Solve two-account investment problems. Find allocation between CD and bonds using system of equations.
Calculate max home price using $1,450/month mortgage at 8% over 30 years. Uses present value of annuity formula.
A ball is thrown from 6.5 ft at 147 ft/sec. Use h(t)=-16t²+147t+6.5=0 to find when it lands. Quadratic formula explained.
Write kinematic equation for vertical position. Find time for bread to reach 16 meters. Quadratic and substitution methods.