Uncle Bruce is baking chocolate chip cookies. He has 36 ounces of dough (with no chocolate) and 15 ounces of chocolate. How much chocolate is left over if he uses all the dough but only wants the cookies to consist of 20% chocolate?
(A) 3
(B) 6
(C) 7.2
(D) 7.8
(E) 9
Answer: B
Source: Veritas Prep
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Uncle Bruce is baking chocolate chip cookies. He has 36 ounces o
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BTGModeratorVI
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Let the total weight of cookies \(= x\)BTGModeratorVI wrote: ↑Tue Mar 31, 2020 5:13 amUncle Bruce is baking chocolate chip cookies. He has 36 ounces of dough (with no chocolate) and 15 ounces of chocolate. How much chocolate is left over if he uses all the dough but only wants the cookies to consist of 20% chocolate?
(A) 3
(B) 6
(C) 7.2
(D) 7.8
(E) 9
Answer: B
Source: Veritas Prep
dough used \(= 36\) ounces, which is \(80\%\) of the total
\(\Longrightarrow \dfrac{80}{100}\cdot x =36 \Longrightarrow x= 45\) ounces
Out of \(45\) ounces, \(20\%\) is chocolate \(\Longrightarrow \dfrac{20}{100}\cdot 45 = 9\) ounces
Thus, leftover chocolate \(= 15 - 9 = 6\) ounces.
Hence, the correct answer is B
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BTGModeratorVI wrote: ↑Tue Mar 31, 2020 5:13 amUncle Bruce is baking chocolate chip cookies. He has 36 ounces of dough (with no chocolate) and 15 ounces of chocolate. How much chocolate is left over if he uses all the dough but only wants the cookies to consist of 20% chocolate?
(A) 3
(B) 6
(C) 7.2
(D) 7.8
(E) 9
Answer: B
Source: Veritas Prep
We can use equivalent ratios.
The cookies will consist of 20% chocolate.
In other words, the cookies will consist of 1/5 chocolate.
We can also say the cookies will consist of 4/5 dough.
This means the cookies are 4 parts dough and 1 part chocolate.
So, the dough to chocolate ratio = 4/1
We have 36 ounces of dough available.
Let c = the number of ounces of chocolate needed.
We now can use equivalent ratios to set up the equation: 4/1 = 36/c
Solve to get c = 9
So, we need to USE 9 ounces of chocolate, which leaves us with 6 ounces REMAINING.
Answer: B
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Brent
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Scott@TargetTestPrep
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Let x = the amount of chocolate to be used so that the cookies consist of 20% chocolate. We have:BTGModeratorVI wrote: ↑Tue Mar 31, 2020 5:13 amUncle Bruce is baking chocolate chip cookies. He has 36 ounces of dough (with no chocolate) and 15 ounces of chocolate. How much chocolate is left over if he uses all the dough but only wants the cookies to consist of 20% chocolate?
(A) 3
(B) 6
(C) 7.2
(D) 7.8
(E) 9
Answer: B
Source: Veritas Prep
x/(36 + x) = 20/100
x/(36 + x) = 1/5
5x = 36 + x
4x = 36
x = 9
Thus, if the cookies are to contain 20% chocolate, 15 - 9 = 6 ounces of chocolate will remain.
Answer: B
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