Question 1

How is a mortgage payment calculated?

Accepted Answer

Mortgage payments use the amortization formula: M = P × [r(1+r)^n]/[(1+r)^n-1], where P is the loan amount, r is the monthly interest rate (annual rate ÷ 12), and n is the total number of monthly payments (years × 12). For example, a $300,000 loan at 6.5% for 30 years results in a monthly payment of about $1,896.

Question 2

How does compound interest work?

Accepted Answer

Compound interest earns interest on both your original principal and on previously earned interest. The formula is A = P(1+r/n)^(nt), where P is principal, r is the annual rate, n is compounding frequency per year, and t is time in years. With monthly contributions, use the extended formula to include regular deposits.

Question 3

How do I calculate BMI?

Accepted Answer

BMI (Body Mass Index) is calculated as weight in kilograms divided by height in meters squared: BMI = kg/m². For imperial units: BMI = (weight in lbs / height in inches²) × 703. Categories: Underweight (<18.5), Normal (18.5-24.9), Overweight (25-29.9), Obese (30+). Note: BMI is a screening tool and doesn't account for muscle mass or body composition.

Question 4

How do I calculate a tip?

Accepted Answer

Multiply your bill by the tip percentage divided by 100. For example, 20% tip on an $85 bill: $85 × 0.20 = $17 tip, making the total $102. Quick trick: find 10% by moving the decimal point left one place, then double it for 20%. To split, divide the total (bill + tip) by the number of people.

Question 5

How do I convert hourly wage to annual salary?

Accepted Answer

Multiply your hourly rate by the number of hours you work per week, then multiply by 52 weeks. For example, $25/hour × 40 hours × 52 weeks = $52,000 per year. To go the other direction, divide annual salary by 2,080 (40 hours × 52 weeks) to get the hourly rate.

Question 6

How do I calculate percent off a price?

Accepted Answer

Multiply the original price by (1 - discount/100). For example, 25% off a $200 item: $200 × (1 - 0.25) = $200 × 0.75 = $150. Your savings would be $50. Quick trick: for 10% off, just move the decimal left; for 25% off, divide by 4; for 50% off, divide by 2.

Question 7

How do I calculate percentages?

Accepted Answer

There are three common percentage calculations: (1) X% of Y = (X/100) × Y, (2) X is what % of Y = (X/Y) × 100, and (3) Percent change = ((New - Old) / Old) × 100. For example, 15% of 200 = 30; 45 is 25% of 180; and going from $50,000 to $55,000 is a 10% increase.

Question 8

How is GPA calculated?

Accepted Answer

GPA = Total Quality Points ÷ Total Credit Hours. Quality Points for each course = Grade Point Value × Credit Hours. Standard scale: A/A+ = 4.0, A- = 3.7, B+ = 3.3, B = 3.0, B- = 2.7, C+ = 2.3, C = 2.0, C- = 1.7, D+ = 1.3, D = 1.0, F = 0.0.

CORE CALCULATION ENGINE

Mortgage

Loan

Interest

Salary

Discount

BMI

Age

Percent

GPA

Tip

HISTORICAL DATA CLUSTER

LIVE_SYSTEM_LOG

MORTGAGE MODULE

Amortization Schedule

Calculation Methodology

LOAN MODULE

Calculation Methodology

COMPOUND INTEREST MODULE

Calculation Methodology

SALARY MODULE

Calculation Methodology

DISCOUNT MODULE

Calculation Methodology

BMI MODULE

Calculation Methodology

PERCENTAGE MODULE

Calculation Methodology

GPA MODULE

Calculation Methodology

AGE MODULE

Calculation Methodology

TIP MODULE

Calculation Methodology

CORE CALCULATION ENGINE

Mortgage

Loan

Interest

Salary

Discount

BMI

Age

Percent

GPA

Tip

HISTORICAL DATA CLUSTER

LIVE_SYSTEM_LOG

MORTGAGE MODULE

Amortization Schedule

Calculation Methodology

LOAN MODULE

Calculation Methodology

COMPOUND INTEREST MODULE

Calculation Methodology

SALARY MODULE

Calculation Methodology

DISCOUNT MODULE

Calculation Methodology

BMI MODULE

Calculation Methodology

PERCENTAGE MODULE

Calculation Methodology

GPA MODULE

Calculation Methodology

AGE MODULE

Calculation Methodology

TIP MODULE

Calculation Methodology

SYSTEM DIAGNOSTICS