Jim can run 5 miles per hour on level ground on a still day

Jim can run 5 miles per hour on level ground on a still day. One windy day, he runs 12 miles with the wind, and in the same amount of time runs 7 miles against the wind. What is the rate of the wind? (Round your answer to the nearest tenth, it necessary.) 5 miles per hour 2.5 miles per how 1.3 miles per hour 19 miles per hour Find the constant of proportionality k, and write the linear function relating the two variables. Suppose that y varies directly with x. When x = 1/3, then y = 4. k = 1/12; y = 1/12 x k = 11/3; y = x + 11/3 k = 12; y = 12x k = 1/4; y = 1/4 x Solve. The velocity v of a falling object (ignoring air resistance) is directly proportional to the time t of the fall. If, after 4 seconds, the velocity is 128 feet per second, what will its velocity be after 7 seconds? 131 foot/second 224 feet/second 221 feet/second 7/32 foot/second Find the constant of proportionality k, and write the linear function relating the two variables. Suppose that y varies inversely with x. When x = 15, then y = 3. k = 5; y = 5x k = 45; y = x/45 k = 45; y = 45/x k = 1/45; y = 1/45x

Solution

35) Let the wind speed be w:

with the wind = w +5

against the wind =5 -w

12/ (w+5) = 7/(5 -w)

12(5 -w) = 7(w +5)

60 -12w = 7w +35

25 = 19w

w = 25/19 = 1.3 miles per hour

Option C)

36) Let the relation ir represented as : y = kx

x = 1/3 ; y=4

4 = k/3

k = 12

So, y = 12x

Option C