What is $6.99^3 - 3.01^3$ approximately equal to?

196Correct answerYour answer236Correct answerYour answer276Correct answerYour answer316Correct answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer D

Correct answer: D

$6.99 \approx 7$ and $3.01 \approx 3$ .
$7^3 = 343$ and $3^3 = 27$ .
$343 - 27 = 316$ .

Worth noting

Cubing magnifies rounding errors: the exact value is about 314.3, still clearly nearest 316. $(7 - 3)^3 = 64$ is the difference cubed, not the difference of cubes.

Concept: Estimating a difference of cubes
Typical timeTypical: 90 s
Your timeYours: —

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What is 6.993−3.0136.99^3 - 3.01^36.993−3.013 approximately equal to?

Explanation

What is $6.99^3 - 3.01^3$ approximately equal to?