Find the quotient of [tex]\frac{-4 a^{-1} b^5}{20 a^2 b^4}[/tex].

A. [tex]-5 a^3 b[/tex]
B. [tex]-\frac{5 b}{a^3}[/tex]
C. [tex]-\frac{b}{5 a}[/tex]
D. [tex]-\frac{b}{5 a^3}[/tex]



Answer :

To find the quotient of the given fraction \(\frac{-4 a^{-1} b^5}{20 a^2 b^4}\), we need to perform the following steps:

### Step 1: Rewrite the terms with positive exponents
The numerator is \( -4 a^{-1} b^5 \). Using the property \( a^{-n} = \frac{1}{a^n} \), the numerator can be rewritten as:
[tex]\[ -4 a^{-1} b^5 = -4 \cdot \frac{1}{a} \cdot b^5 = -\frac{4 b^5}{a} \][/tex]

The denominator is \( 20 a^2 b^4 \). This is already in a simple form:
[tex]\[ 20 a^2 b^4 \][/tex]

Therefore, the fraction becomes:
[tex]\[ \frac{-\frac{4 b^5}{a}}{20 a^2 b^4} \][/tex]

### Step 2: Simplify the complex fraction
To simplify this complex fraction, multiply both the numerator and the denominator by \( a \):
[tex]\[ \frac{-4 b^5}{a} \div 20 a^2 b^4 = \frac{-4 b^5}{a} \cdot \frac{1}{20 a^2 b^4} = \frac{-4 b^5 \cdot 1}{a \cdot 20 a^2 b^4} = \frac{-4 b^5}{20 a^3 b^4} \][/tex]

### Step 3: Combine the constants and variables
Now, combine and simplify the constants and the variables:
[tex]\[ \frac{-4 b^5}{20 a^3 b^4} = -\frac{4 b^5}{20 a^3 b^4} \][/tex]

### Step 4: Simplify the constants
[tex]\[ - \frac{4}{20} = -\frac{1}{5} \][/tex]
So the fraction simplifies to:
[tex]\[ -\frac{1}{5} \cdot \frac{b^5}{a^3 b^4} \][/tex]

### Step 5: Simplify the variables
Simplify \(\frac{b^5}{b^4}\):
[tex]\[ \frac{b^5}{b^4} = b^{5-4} = b \][/tex]

Combining this with the remaining terms, we get:
[tex]\[ -\frac{1}{5} \cdot \frac{b}{a^3} = -\frac{b}{5 a^3} \][/tex]

So, the simplified quotient of the given fraction is:
[tex]\[ -\frac{b}{5 a^3} \][/tex]

Therefore, the correct answer is:
[tex]\[ -\frac{b}{5 a^3} \][/tex]