A and B are two alloys of copper and tin prepared by mixing the respec

Question

A and B are two alloys of copper and tin prepared by mixing the respective metals in ratio of 5:3 and 5:11 respectively. If the alloy A and B are mixed to form a third alloy C with an equal proportions of copper and tin what is the ration of alloys A and B In the new alloy C?

A 3:5
B 4:5
C 3:2
D 2:3
E 15:17

Show Answer

Official Answer

C

A 3:5
B 4:5
C 3:2
D 2:3
E 15:17

Ankyta333 · Accepted Answer

Given:
 A B C= A+B
Copper 5a 5b 5a + 5b
 Tin 3a 11b 3a + 11b 
Total 8a 16b

In C, the ratio of Copper and Tin is Equal. 
So 5a + 5b = 3a +11b --> 2a = 6b --> a/b =3/1 .........(1)

Now we are asked what is the ratio of alloys A and B in new alloy C. 
So we need Alloy A/ Alloy B --> (8a)/(16b) i.e. we need to find a/2b and using (1) we get
a/2b = 1/2 * a/b = 1/2 * 3/1 = 3/2.

adityasuresh · Answer

A and B are two alloys of copper and tin prepared by mixing the respective metals in ratio of 5:3 and 5:11 respectively. If the alloy A and B are mixed to form a third alloy C with an equal proportions of copper and tin what is the ration of alloys A and B In the new alloy C?

A 3:5
B 4:5
C 3:2
D 2:3
E 15:17

Show Answer

Official Answer

C

A 3:5
B 4:5
C 3:2
D 2:3
E 15:17

Alloy A ratio = 5:3 Copper = 5/8 = 10/16
Alloy B ratio = 5:11 Copper = 5/16 = 5/16
Final Alloy C = 1:1 Copper = 1/2 = 8/16

Make denominator common
Copper average in alloy c = 8
Using alligation
POV of copper
A = 10 B = 5

C = 8
 (Average)
8 - 5 10 - 8
 = 3 : 2
 C

twobagels · Answer

\frac{5}{8} *x +  \frac{5}{16} *y =  \frac{3}{8} *x +  \frac{11}{16} *y

\frac{2}{8} *x =  \frac{6}{16} *y

\frac{x}{y} =  \frac{3}{2}

pablotc89 · Answer

I got it this way, and I found it very intuitive:

Copper is in mix A in the ratio 5/8
Copper is in mix B in the ratio 5/16

So the question is how many of A and B I need to get a ratio 1/2 which is the same as:

(5A/8 + 5B/16) / (A+B) = 1/2

It is divided by (A+B) because is the total amount mixed

10A + 5B = 8A+8B
2A = 3B
A/B = 3/2

Hope it helps!

Can,Will · Answer

need help
can anyone solve this with allegation diagram ??

divyadna · Answer

Posted from my mobile device

bumpbot · Answer

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A and B are two alloys of copper and tin prepared by mixing the respec

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A and B are two alloys of copper and tin prepared by mixing the respec

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