Module 1: Basic Concepts - Logarithms - Practice Problems
- Instructions:
- Work these problems on a sheet of paper and check your answers against those provided below.
-
#1
-
Express the following logarithmic functions as exponential functions.
-
Log10 (150) = x
-
Log10 (55) = x
-
Ln (500) = x
-
Ln (65) = x
-
Log10 (150) = x

-
Answer:
-
10x = 150
-
10x = 55
-
ex = 500
-
ex = 65
-
10x = 150

-
Answer: i. x = 3
- Solution:
- Log10 (1,000) = x can be rewritten as
10X = 1000 where x = 3

- Answer:
- ii. x = 1.7709
- iii. x = 2.4771
- Solution:
-
#3
-
Simplify the following:
-
Log10 (ab)
Log10 (a)
-
Log10 (ab) + Log10 (b)

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Log10 (50) + Log10 (265)
Log10 (315)
-
Log10 (ab)

-
Answer: i. Log10 (b)
- Solution:
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- Answer: ii. Log10 (a) +2 Log10 (b)
- Solution:
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- Answer: iii. 4
- Solution:
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- Answer: iv. 1.6239
- Solution:
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- Solution:

-
Answer: i. x = 96.41
- Solution:
- i. 4.8e3 = 4.8
20.086 = 96.41

- Answer: ii. 1,370.29
- Solution:

- Answer: iii. 1,272.91
- Solution:
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- Solution:

-
Answer:
- i. x = 6.91
- ii. x = 3

- Answer: iii. x = 6.015
- Solution:
- iii. 4.852 + 1.163 = 6.015
- i. x = 6.91
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