Question

Alloy's weight is 12 1/2 kg, ratio of zinc and copper
is 1:4. find the weight of copper

Answer 1

Direct Answer:

10 kg

Given:

The weight of the alloy is 12 and a half kilo.

The ratio of zinc and copper is 1:4.

To Find:

the weight of copper in the alloy.

Solution:

In this question it is given that the weight of the alloy is 12 and half kilo. It is also given that the constituents are in the ratio 1:4.

Let's assume that the amount of zinc present in the alloy is 1x and the amount of copper present in the alloy is 4x. Forming an equation from the given data:

$\sf{\implies1x + 4x = 12\dfrac{1}{2}}kg$

Adding the components of the LHS and simplifying the fraction in the RHS, we get:

$\sf{5x = \dfrac{25}{2}}$

Transposing x to the power of the equation, we get:

$\sf{x =\dfrac{25}{2}\times\dfrac{1}{5}}$

$\sf{ x= \dfrac{5}{2}}$

So, we can conclude that the value of x is 5/2.

Now we have to find the weight of copper which is 4x. Substituting the value of x into the the expression,

$\sf{4x = 4\times\dfrac{5}{2}}$

$\sf{ = 2\times5}$

$\sf{ = 10kg}$

Therefore copper constitutes in the alloy at the weight of 10 kilo.