Question

50kg of an alloy of lead and time contains 60% of lead . how much lead must be melted into it to mack the alloy contain 75% of lead ?​

Answer 1

Answer:

30 kg

Step-by-step explanation:

So whenever this kind of question are given ,

Quickly jot down the values u r given with ,

That is

50 kg of alloy +tin gives u with 60% of lead .

To find : how much lead to be added to make it 75%

So , let's find lead content ,

That is

50 × 60/100

= 30kg

Let's assume kg(s) of lead added to be x

Then , total weight of alloy would be = 50+x kg

Then , the weight of lead would increase by 30+x kg .

Now let's take out value of 75%

That is

75/100 = 0.75

Now,

30+x = 0.75(50+X)

30+x = 37.5+0.75x

x-0.75x = 37.5–30

0.25 = 7.5

x = 7.5/0.25

x = 30kg

Hence , 30kg should be added to make the content of lead as 75% .