Cost is expressed by the formula tb^4. If b is doubled and t remains

Question

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

drdprajapati1987 · Answer

C1= tb^4

Let B be new variable 
therfore B= 2b

C2 = t B^4 
 = t (2b) ^4
 = t · 16 · b^4

hence ---E

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Abhishek009 · Answer

C = tb^4

Plug in and check

t = 1  &  b = 2

So,  C = 1*2^4

Or,  C = 1*16

Or,  C = 16

b = 4  &  t = 1

So,  C = 1*4^4

Or,  C = 1*256

Or,  C = 256

Or,  \frac{256}{16}

Or, 16 , Answer must be (E)

sujoykrdatta · Answer

Since b is doubled (t unchanged), the new value becomes:  t * (2b)^4 = 16 * tb^4

Thus, the new value is  16 times as great as  the original cost

However, if you ask me - "how many times greater than?", i'd be inclined to think it is  15 times greater than

For example: Say X has 2 chocolates
If I have three times as many as X does, then I definitely have 3*2 = 6
However, if I have three times greater than X, then I have 2 + 3*2 = 8

Reference:  https://english.stackexchange.com/questions/7894/x-times-as-many-as-or-x-times-more-than

Mo2men · Answer

Let t=1 & b=1..cost=1

Let t=1 * b=2...cost =16

Then the cost is 16 times the initial one

Answer: E

Cost is expressed by the formula tb^4. If b is doubled and t remains

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Cost is expressed by the formula tb^4. If b is doubled and t remains

Prep Toolkit

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