In a 5/6 pound mixture of sand and gravel, 1/4 pound is gravel.

How much gravel is there in a 1-pound mixture?

1/4lbs of gravel is in 5/6lbs of mixture

xlbs of gravel is in 1lbs of mixture

1/4:5/6=x:1, 1/4*1=5/6*x

5/6*x=1/4, x = (1/4) / (5/6)

x=3/10

In 1 pound of mixture of sand and gravel, 3/10 pound is gravel.

Total mass of mixture is given as 5/6 pound, in which 1/4 pound is gravel. Amount of sand in the mixture will be 5/6 - 1/4 = 7/12 So, the ratio of sand to that of gravel in given mixture is 7/12:1/4 = 7:3. i. e every 10 parts of mixture contain 7 parts of sand and 3 parts of gravel. If we are given 1-pound of same mixture, it will contain 1 * 3/10 pound gravel, i. e. 0.3 pound.