Basic Logarithms
Properties of Logarithms
Logarithmic Equations
Exponential Equations
Compound Interest
100

Log 10 (1/10) = ?

-1

100

Expand the logarithmic expression:

Log 1000x = ?

3 + log x

100

Solve for x:

Log 4 (x + 7) = 2

x = 9
100

Solve for x:

3x = 107

x = 4.25

100

$40,000 is invested at 5% and compounded annually for 5 years.

What is the final balance?

$51,051.26

200

Log 3 (sqrt(3)) = ?

1/2

200

Expand the logarithmic expression:

Ln (e8 / 13) = ?

8 - ln 13

200

Solve for x:

Log (x + 8) + Log 6 (x + 3) = 1

x = -2

200

Solve for x: 

70.9x = 519

x = 3.57


200

$3000 is invested at 8% and compounded continuously for 7 years.

What is the final balance?

$5252.02

300

Log 81 0 = ?

No solution

300

Expand the logarithmic expression:

Ln (4th root of x) = ?

1/4 ln x

300

Solve for x:

Log 6 (x + 28) - Log (x-7) = 2

x = 8

300

Solve by expressing each side as the power of the same base:

3(x-6 / 8) = sqrt(3)

x = 10

300

What investment would reach a final balance of $50,000 if it was compounded continuously at a rate of 7% for 19 years?

$13,223.86

400

Log 27 3 = ?

1/3


400

Rewrite Log 13 in base e

ln 13 / ln 8

400

Solve for x:

ln x + ln (x - 2) = ln 3

x = 3

400

Solve for x:

53x + 6 = 5x - 7

x = -13/2

400

How long would it take for $50,000 to reach $125,000 if it was compounded at 10.4% daily?

8.8 years

500

2Log 2 (3) = ?


3

500

Expand the logarithmic expression:

Log (100z)

2 +  log z

500

Solve for x:

Log (5x - 4) = Log (x + 3) + Log 6

No solution


500

Solve for x:

e2x - 8ex + 7 = 0

x = 0 

&

x = 1.95

500

How long would it take for a $2800 investment compounded at 18.3% continuously to triple in value?

6 years