AP Env Math study guide
Approximate populations to know
World - 8,161,972,572 people (8.1 × 10^9)
United States -345,426,571 people (3.4 × 10^8)
China - 1,419,321,278 people (1.41 × 10^9)
India - 1,450,935,791 people (1.45 × 10^9)
Indonesia - 279,798,049 people (2.7 × 10^8)
Brazil - 217.0 million people (2.17 × 10^8)
Metrix prefixes
T tera- 10^12 trillion | |||
G | giga- | 10^9 | billion |
M | mega- | 10^6 | million |
k | kilo- | 10³ | 1000 |
h | hecto- | 10² | 100 |
da | deka- | 10^1 | 10 |
d | deci- | 10^-1 | .1 |
c | centi- | 10^-2 | .01 |
m | milli- | 10^-3 | .001 |
micro- | 10^-6 | one millionth | |
n | nano- | 10^-9 | one billionth |
p | pico- | 10^-12 | one trillionth |
Common statistical terms
Mean - mathematical average
Median - 50th percentile (middle value_
Mode - most frequent number
Converting formulas
AREA = L x W
VOLUME = L x W x H
1m = 1000mm
1m³ = ____ mm³
1³ m³ = 1000³ mm³
(10³)³=10^9 mm³
Density = mass/volume
Growth rate calculations
Growth rate = [CRUDE BIRTH RATE + immigration] - [(CRUDE DEATH RATE + emigration)]
CBR = crude birth rate = # births per 1000, per year
CDR = crude death rate = # deaths per 1000, per year
(CBR-CDR) / 10 = percent change
Percent change
(where V = value)
The rate of change (percent change) from one period to another =
[(Vpresent - Vpast / Vpast] x 100
Percent difference
Percent difference = (First Value - Second value) / (First Value + Second value) / 2 × 100%
Rule of 70
Doubling time = 70/annual growth rate
Extras I don’t feel like making whole categories for
Population density = number of individuals / unit area
Npp (net primary productivity) = GPP (gross primary productivity) - R (respiration)