Question

a bar of metal contains 20% silver and another bar contains 12% silver how many grams of teach must be taken to make a 40 gram bar containing 14 whole 1/2% silver​

Answer 1

In the 40g bat , let x g be of the first bar and (40-x) be of the second bar .

Then silver content in the first bar = 20% of X = 20x/100

Silver content in the second bar

= 12% of (40-x)

=> 12/100×(40-x)

=> 12×(40-x)/100

Total silver in 40 g bar

= X/5+12×(40-x)/100

Given ,

Silver in 40 g bar = 29/2% of 40

= 29/200×40

=> 29/5

According to the question:-

20X/100+12×(40-x)/100 = 29/5

20x+480-12x /100 = 29/5

8x + 480 /100 = 29/5

8x +480= 29 / 5 × 100

8x + 480 = 29×20

8x + 480 = 580

8x = 580-480

8x = 100

X = 100/8

X = 25/2

Hence 25/2 or 12 whole 1/2 of the first bar and 25/2-40 = 27 whole 1/2 of the second bar be taken .

Answer 2

/

Step-by-step explanation:

1/2/12 from l and 1/2 /27