# How did I get this wrong?

Write 8(6)/4(3)*2(5) as a single power of 2.

The numbers in brackets are the small numbers at the top. I got 2(7) but my revision book is telling me it's 2(17). What did I do wrong?

Relevance

If it's written just like that, then the order of operations says you mean:

(8^6 / 4^3) * 2^5

= (2^18 / 2^6) * 2^5

= 2^12 * 2^5

= 2^17

• this is best done by putting all the values as powers of 2 on the same line

8^6/4^3*2^5

= 2^(3•6) / 2^(2•3)•2^5

= 2^18 / 2^6•2^5

= 2^18 / 2^11

= 2^7

the book has a typo unless it should be

(2^(3•6) / 2^(2•3))•2^5

Then the 2^5 belongs in the numerator, and the book is correct

• Anonymous
9 years ago

The small numbers at top are called exponents.

8^6 / (4^3)(2^5)

(2*2*2)^6 / (2*2)^3(2^5)

(2^3)^6 / (2^2)^3(2^5)

2^(3*6) / 2^(2*3)(2^5)

2^18 / (2^6)(2^5)

2^18 / 2^(6+5)

2^18 / 2^11

2^(18-11)

2^7

You're correct and your book is wrong.

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EDIT: It's unclear whether the problem is [(8^6)/(4^3)]*(2^5) with the 2^5 separate from the fraction or if it is (8^6)/[(4^3)(2^5)] with the 2^5 in the denominator.

[(8^6)/(4^3)]*(2^5)

= {[(2*2*2)^6]/[(2*2)^3]}*(2^5)

= {[(2^3)^6]/[(2^2)^3]}*(2^5)

= {[2^(3*6)]/[2^(2*3)]}*(2^5)

= [(2^18)/(2^6)]*(2^5)

= [2^(18-6)]*(2^5)

= (2^12)*(2^5)

= 2^(12+5)

= 2^17

Next time, use parenthesis to describe it clearly.

• Anonymous
9 years ago

8(15)= 2(3) duh.

Source(s): a calculator.