The time required to do a job varies inversely as the number of people working on it, it takes five hours for seven volunteers to pick up the rubbish from 1 mile away. how long will it take 10 volunteers to complete the job

3.5 hours

Step-by-step explanation:

let t represent time and n the number of volunteers.

Given that t varies inversely as n then the equation relating them is

t = ← k is the constant of variation

To find k use the condition t = 5 when n = 7, then

k = tn = 5 × 7 = 35, thus

t = ← equation of variation

When n = 10, then

t = = 3.5 hours

in 1995, potato plants were taken into space aboard the space shuttle columbia.

step-by-step explanation:

this is a direct variation proportion. y = kx

y is the total amount due, k is the constant of variation, and x is the number of texts sent.

plug in the 3.20 and the 16 to solve for the "k". this is the constant of proportionality. it is the value that will not change.

3.20 = k(16). solving you get $.20 per text.

the equation would then be y = .20x