Difference between revisions of "2020 AMC 8 Problems/Problem 1"

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==Solution 4==
 
==Solution 4==
  
We are given that <math>4w:s</math> and <math>2s=l</math> which we combine to get <math>8w:2s:l</math>. Letting all the variables equal <math>3</math>, we find that the answer is <math>3\cdot 8=\textbf{(E)}\ 24</math>.
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We are given that <math>4w:s</math> and <math>2s=l</math> which we combine to get <math>8w:2s:l</math>. Letting all the variables equal <math>3</math>, we find that the answer is <math>3\cdot 8=\boxed{\textbf{(E) }24} 24</math>.
  
 
-franzliszt
 
-franzliszt
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==Solution 5==
 
==Solution 5==
  

Revision as of 19:54, 19 November 2020

Luka is making lemonade to sell at a school fundraiser. His recipe requires $4$ times as much water as sugar and twice as much sugar as lemon juice. He uses $3$ cups of lemon juice. How many cups of water does he need?

$\textbf{(A) }6 \qquad \textbf{(B) }8 \qquad \textbf{(C) }12 \qquad \textbf{(D) }18 \qquad \textbf{(E) }24$

Solution 1

Luka will need $3\cdot 2=6$ cups of sugar and $6\cdot 4=24$ cups of water. The answer is $\boxed{\textbf{(E) } 24}$.

Solution 2

Let $W, S,$ and $L$ represent the number of cups of water, sugar, and lemon juice that Luka needs for his recipe, respectively. We are given that $W=4S$ and $S=2L$. Since $L=3$, it follows that $S=6$, which in turn implies that $W=24 \implies\boxed{\textbf{(E) }24}$.
~junaidmansuri

Solution 3

We have that $\textsf{lemonade} : \textsf{water} : \textsf{lemon juice} = 8 : 2 : 1,$ so we have $3 \cdot 8 = \boxed{\textbf{(E) }24}.$

[pog]

Solution 4

We are given that $4w:s$ and $2s=l$ which we combine to get $8w:2s:l$. Letting all the variables equal $3$, we find that the answer is $3\cdot 8=\boxed{\textbf{(E) }24} 24$.

-franzliszt

Solution 5

Put the numbers in ratios $4w:s$ and $2s:lj$ when w = water, s = sugar, and lj = lemon juice. then since we know there is $3$ cups of lemon juice, do the math. $3\cdot2\cdot4=6\cdot4=24$

~ bsu1

Video Solution

https://youtu.be/FPC792h-mGE

~savannahsolver

See also

2020 AMC 8 (ProblemsAnswer KeyResources)
Preceded by
First problem
Followed by
Problem 2
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
All AJHSME/AMC 8 Problems and Solutions

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we just get 4*3*2=24$ which is E -oceanxia