Question

What is the value of x in the expression log10(20 * x)=3?

Answer 1

a^x = N ⇔ x = logarithm of N to the base a

Hence log10(20 * x)=3 ⇒ 20*x = 10³ ⇒ x=50

Answer 2

We first rewrite the question.

㏒₁₀(20x) = 3

We will use the following logarithm formula:

㏒ₐᵇ = c

Hence :

a^c = b

Doing this we have :

10³ = 20x

1000 = 20x

x = 1000/20 = 50

x = 50