We are given relation between distance( in kilometers) travelled and number of hours taken by an Albatross bird. Distance in kilometers taken by variable d. Number of hours by t. And situation is given d=50t. We know, direct relation formula y= kx read as y is directly proportional to x. And k is the constants of proportionality. In the given fuction y is taken by variable d and x is taken by variable t. If we compare d=50t by y = mx, the value of k is 50. Therefore, constant of proportionality is 50. Constant is a number that never change it's value. Therefore, constant of proportionality is just 50. But we can say variables d and t are two variables those are directly proportional to each other. Constant of proportionality is actually unit rate of change. For the given situation constant of proportionality is the number of km travelled in per unit time (in 1 hour.) If we divide 400km 8 hours, we get 400/8 = 50 km per hour. Therefore, variables of proporation are d and t and relation between them is " they are directly proportional to each other". And the constants of proportionality is just 50.
