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

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

SantoshSukumaran · Answer

Can some assist with soln

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freedom128 · Answer

Hi. This explanation will help to tackle the problem. Kindly leave kudo

, thanks . A has \frac{5}{8} copper and \frac{3}{8} tin (5:3). B has \frac{5}{16} copper and \frac{11}{16} tin (5:11). C is a mixture of A (i.e. a unit) and B (i.e. b unit) so that C's copper and tin have equal proportion (1:1). Thus, --> Copper in C = \frac{5}{8}a + \frac{5}{16}b --> Tin in C = \frac{3}{8}a + \frac{11}{16}b Copper in C = Tin in C (equal proportion) \frac{5}{8} a + \frac{5}{16} b = \frac{3}{8} a + \frac{11}{16} b \frac{2}{8} a = \frac{6}{16} b 2a = 3b a/b = 3:2 Answer is (C)

gracie · Answer

5A/8+5B/16=(A+B)/2→
A/B=3/2=3:2
C

testtakerstrategy · Answer

Is there a way to do this problem using the scale method? If so , could someone post that solution.

Fdambro294 · Answer

When encountering mixture questions like these, I like to choose 1 of the 2 elements and focus on that.

A --- Copper : Tin : TOTAL = 5 : 3 : 8

A has 5/8 of copper per Unit Part

B --- Copper : Tin : TOTAL = 5 : 11 : 16

B has 5/16 of copper per Unit Part

Final Mixture C --- Copper : Tin: TOTAL = 1 : 1 : 2

C will have 1/2 of copper per Unit Part

2nd) Make an Equation for the Amount of Copper that is going into the Final Alloy C

A = Unit Parts of A that are going into the Mixture C
B = Unit Parts of B that are going into the Mixture C

A + B = C Final Mix that will only include the Unit Parts of A and B

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

Since C = A +B ----- Substitute

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

Performing the Algebra you end up with

(5/8 - 1/2) * A = (1/2 - 5/16) * B

1/8 * A = 3/16 * B

then Divide Each Side by 3, and you will get the Ratio Form set up as an Equality ----

A / 24 = B / 16

A / 3 = B / 2 ------ this is the Same way of Writing: Ratio of A : B = 3 : 2

Answer C

ZZhang · Answer

Weighted Averages Method

Copper in A is 10/16
Copper in B is 5/16
Want final mixture of 8/16

Multiply by 16 to get weighted average of 10 to 8 to 5.

Difference of A from average is 2 and difference of B from average is 3.
Hence ratio required for A to B is 3:2

Calculation: (10-8)/(8-5) = 2/3. Hence ratio is 3/2.

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

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