Math Destroyer 2017 Test 7 question

[dannys00]

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I'm stuck on many questions, but I'm lost on Test 7, Question 32 (page 83):
Evaluate [8^6 - 4^7] / 2^14
The answer is 15, but the explanation on the back doesn't explain how (2^18 - 2^14) / 2^14 turns into 2^4 - 1
Is there some type of exponet rule I'm missing?
Thank you in advance.

 

[zToothinator]

Fractions with a common denominator can be split up so (2^18 - 2^14) / 2^14 turns into (2^18 / 2^14) - (2^14 / 2^14). (2^18 / 2^14) simplifies to 2^4 since you can subtract exponents when dividing. (2^14 / 2^14) simplifies to 1 so you're left with 2^4 - 1 = 15

 

[dannys00]

Fractions with a common denominator can be split up so (2^18 - 2^14) / 2^14 turns into (2^18 / 2^14) - (2^14 / 2^14). (2^18 / 2^14) simplifies to 2^4 since you can subtract exponents when dividing. (2^14 / 2^14) simplifies to 1 so you're left with 2^4 - 1 = 15

Awesome thank you!!!