Solve Complex Fraction: (4⁰×6⁷)/(36⁴×9⁰) Simplified

Question

406736490=? \frac{4^0\cdot6^7}{36^4\cdot9^0}=\text{?}

Video Solution

Solution Steps

00:00 Solve
00:03 According to the laws of exponents, any number raised to the power of 0 equals 1
00:06 As long as the number is not 0
00:09 We will use this formula in our exercise
00:30 Let's break down 36 to 6 squared
00:36 When there's a power of a power, the exponents are multiplied
00:41 We will use this formula in our exercise, and multiply between the powers
00:53 When dividing powers with equal bases
01:01 The power of the result equals the difference of the exponents
01:04 We will use this formula in our exercise, subtract the exponents
01:09 For any number/fraction with a negative exponent
01:12 We can flip the numerator and denominator to get a positive exponent
01:15 We will use this formula in our exercise
01:19 And this is the solution to the question

Step-by-Step Solution

First we'll use the fact that raising any number to the power of 0 gives the result 1, mathematically:

X0=1 X^0=1

We'll apply this to both the numerator and denominator of the fraction in the problem:

406736490=1673641=67364 \frac{4^0\cdot6^7}{36^4\cdot9^0}=\frac{1\cdot6^7}{36^4\cdot1}=\frac{6^7}{36^4}

Next we'll note that -36 is a power of the number 6:

36=62 36=6^2

And we'll use this fact in the denominator to get expressions with identical bases in both the numerator and denominator:

67364=67(62)4 \frac{6^7}{36^4}=\frac{6^7}{(6^2)^4}

Now we'll recall the power rule for power of a power to simplify the expression in the denominator:

(am)n=amn (a^m)^n=a^{m\cdot n}

And we'll also recall the power rule for division between terms with identical bases:

aman=amn \frac{a^m}{a^n}=a^{m-n}

We'll apply these two rules to the expression we got above:

67(62)4=67624=6768=678=61 \frac{6^7}{(6^2)^4}=\frac{6^7}{6^{2\cdot4}}=\frac{6^7}{6^8}=6^{7-8}=6^{-1}

Where in the first stage we applied the first rule we mentioned earlier - the power of a power rule and simplified the expression in the exponent of the denominator term, then in the next stage we applied the second power rule mentioned before - the division rule for terms with identical bases, and again simplified the expression in the resulting exponent,

Finally we'll use the power rule for negative exponents:

an=1an a^{-n}=\frac{1}{a^n}

And we'll apply it to the expression we got:

61=16 6^{-1}=\frac{1}{6}

Let's summarize everything we did, we got that:

406736490=16 \frac{4^0\cdot6^7}{36^4\cdot9^0}=\frac{1}{6}

Therefore the correct answer is A.

Answer

16 \frac{1}{6}