1.6. Percentages

Question 1

How to calculate what the percentage increase is given a numerical increase and the original value…

Answer 1

Percentage increase = (Increase / Original price) * 100

Question 2

How to calculate what the percentage decrease is given a numerical increase and the original value…

Answer 2

Percentage decrease = Decrease / Original price) * 100

Question 3

Simple interest

Answer 3

I = (P * R * T) / 100

I = Interest gained
P = Price/Sum of money invested
T = Time (years invested
R = % interest

Question 4

Compound interest

Answer 4

P(1 + r/100)^n

P = Price/ Sum of money invested
r = % interest
n = number of years