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I have 4 math questions that I don't understand. Please help!?






b^-3=1/216 b=?

743.8 × 103=?
36 ÷ 10–3=?
What is (2.1 × 103) × (4 × 10–7 )?


User Ron Skufca
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1 Answer

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-- A negative exponent means the number is in the denominator.
b⁻³ means 1/b³ .
So 1/b³ = 1/216 . You can do it now.

-- If that number is " 10³ ", it means 1,000 .
If that number is " 103 " and you can't remember
how to do multiplication with a pencil, then you'll
have to use your calculator.

-- Again ... 10⁻³ means 1/10³ or 1/1000 .
So the problem is really 36 divided by 1/1000 .
Be very careful. That means 36 x 1000 .

-- To multiply powers that have the same base,
you add the exponents.

Example: 10⁴ times 10⁵ = 10⁹ .

This question can be rearranged as (2.1 x 4) x (10³ x 10⁻⁷)

(10³) times (10⁻⁷) is 10⁻⁴ .

User Mirswith
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6.4k points