There are two bars of gold-silver alloy. The first bar has 2 parts of gold and 3 parts of silver, and the other has 3 parts of gold and 7 parts of silver. If both bars are melted into an 8 kg bar with the final ratio of 5:11 (gold to silver), what was the weight of the first bar?

Answer : The weight of first bar is, 1 kg

Explanation :

Let the weight of first bar and second bar be, x and y.

The ratio of gold and silver in first bar is, 2 : 3

The ratio of gold and silver in second bar is, 3 : 7

The final ratio of gold and silver in first and second bar is, 5 : 11

Total weight of bar = 8 kg

The equations will be:

      ..........(1)

      ..........(2)

Solving both the equations, we get:

      ..........(3)

      ..........(4)

Now we are multiplying equation 3 by 6 and equation 4 by 4, we get:

      ..........(5)

      ..........(6)

Now we are subtracting equation 5 from 6, we get the value of 'y'.

y = 7

Now put the value of 'y' in equation 5, we get the value of 'x'.

x = 1

Thus, the weight of first bar and second bar is, 1 kg and 7 kg respectively.

for step 7 table c on the lab "newtons law of action"   the average time it took the car to travel .25 meters   was 1.92 seconds.

the average time it took the car to travel 0.50 meters was 2.61 seconds

hope this : )