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Comment on Combining Solutions W and X
50+0.8x = 0.4(250+x)
Yes, that's the equation we
Yes, that's the equation we derived in the video.
Hi Bent,
I find your approach of solving Mixture problems with diagrammatic representation very easy.Thank You.
Can you please help with the following problem:
Two alloys A and B are composed of two basic elements. The ratios of the compositions of the two basic elements in the two alloys are 5 : 3 and 1 : 2, respectively. A new alloy X is formed by mixing the two alloys A and B in the ratio 4 : 3. What is the ratio of the composition of the two basic elements in alloy X ?
(A) 1 : 1
(B) 2 : 3
(C) 5 : 2
(D) 4 : 3
(E) 7 : 9
Tricky question!
Tricky question!
If you like the mixture technique that's shown in the video, then here's one approach:
Let's say the alloys are composed of gold and silver (in that order)
So, alloy A has a gold to silver ratio of 5 : 3
In other words, this alloy is 5/8 gold
Alloy B has a gold to silver ratio of 1 : 2
In other words, this alloy is 1/3 gold
"A new alloy X is formed by mixing the two alloys A and B in the ratio 4 : 3"
Let's combine 4 cups of alloy A with 3 cups of alloy B.
Since alloy A is 5/8 gold, then the amount of gold in 4 cups of alloy A = (5/8)(4) = 5/2 = 2.5 cups
Since alloy B is 1/3 gold, then the amount of gold in 3 cups of alloy B = (1/3)(3) = 1 cup
So, the TOTAL amount of combined gold = 2.5 + 1 = 3.5 cups.
The new mixture has a TOTAL volume of 7 cups.
If 3.5 cups is gold, then the remaining 3.5 cups must be silver.
"What is the ratio of the composition of the two basic elements in alloy X ?"
We get 3.5 : 3.5, which is the same as 1:1
Answer: A
:D :D
I had a smile going through your explanation.
You make tricky things so easy! Thankieeee
Brent,
Could you explain me the exercise #201 of OG17, please?
Thanks,
Pedro
Here's my solution: https:/
Here's my solution: https://gmatclub.com/forum/a-sequence-of-numbers-a1-a2-a3-is-defined-as-...
Cheers,
Brent
Hi Brent,
can you please solve this question, using the technique as in above video.
Jackie has two solutions that are 2 percent sulfuric acid and 12 percent sulfuric acid by volume, respectively. If these solutions are mixed in appropriate quantities to produce 60 liters of a solution that is 5 percent sulfuric acid, approximately how many liters of the 2 percent solution will be required?
Thanks
Here's my full solution with
Here's my full solution with sketches: https://gmatclub.com/forum/jackie-has-two-solutions-that-are-2-percent-s...