Cost is expressed by the formula \(tb^4.\) If \(b\) is doubled and \(t\) remains the same, the new cost is how many times greater than the original cost?
(A) 1.2
(B) 2
(C) 6
(D) 8
(E) 16
[spoiler]OA=E[/spoiler]
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Cost is expressed by the formula \(tb^4.\) If \(b\) is doubled and \(t\) remains the same, the new cost is how many time
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orthodoxparadox
- Junior | Next Rank: 30 Posts
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- Joined: Sat May 30, 2020 10:48 pm
Let \(t'\) and \(b'\) be the new parameters.
So,
\(t'\ =\ t\) and \(b'\ =\ 2\ \cdot\ b\)
New cost = \(t'\ \cdot\ b'^4\ =\ t\cdot\left(2\cdot b\right)^4\ =\ t\cdot16\cdot b^4\ =\ 16tb^4\)
So, the answer is 16 E
So,
\(t'\ =\ t\) and \(b'\ =\ 2\ \cdot\ b\)
New cost = \(t'\ \cdot\ b'^4\ =\ t\cdot\left(2\cdot b\right)^4\ =\ t\cdot16\cdot b^4\ =\ 16tb^4\)
So, the answer is 16 E
