Question

The ratio of zinc and copper in an alloy is 7:9 . if the weight of copper in the alloy is 11.7kg , Find the weight of zinc in it​

Answer 1

Solution:

In the above question, we are given with a certain ratio of amount of zinc and copper in an alloy. Also, the actual amount of copper in that alloy is given. We have to find the weight of zinc in it.

• Ratio of zinc and copper is 7 : 9
• Weight of copper in the alloy = 11.7 kg

As we are given with 3 out of 4 elements in a proportion, we can plug the values to get the 4th i.e. weight of zinc.

So, let consider the weight of zinc be x.

Then,

➝ $\sf{ \dfrac{7}{9} = \dfrac{x}{11.7} }$

Cross multiplying,

➝ $\sf{9x = 11.7 \times 7}$

Dividing 9 from both sides of the equation,

➝ $\sf{x = \dfrac{11.7 \times 7}{9} }$

➝ $\sf{x = 1.3 \times 7}$

Then, x = 9.1 (Answer)

So the weight of the zinc in the alloy is 9.1 kg. And we are done !!

Answer 2

Answer:

Given:-

• Ratio of zinc and copper in a alloy = 7:9
• Weight of copper in the alloy = 11.7 kg

To find:-

Weight of zinc in it.

Solution:-

Let the weight of zinc in it be ‘x’. Then,

ATQ,

7/9 = x/11.7

$\Longrightarrow$ x =

$\frac{11.7 \times 7}{9} </p><p>= \frac{81.9}{9} \\ \\ </p><p>= 9.1$

Therefore, weight of zinc in it is 9.1 kg.