The variable z is directly proportional to x, and inversely proportional to y. when x is 16 and y is 5, z has the value 16. what is the value of z when x= 21, and y= 14 round to at least the thousandths place if needed.

z = 7.5

Step-by-step explanation:

Given that z is directly proportional to x and inversely proportional to y then the equation relating them is

z = ← k is the constant of proportionality

To find k use the condition when x = 16, y = 5, z = 16, then

k = = = 5

z = ← equation of proportionality

When x = 21, y = 14, then

z = = 7.5

first option

a function is a relation in which an input is paired with exactly one output.

so, let's find the right answer.

in our first option, our inputs are january, february, and march. the outputs are 30, 28, and 25. each input has it's own output. this is correct!

our second option we know is incorrect, because ms. valverade has two outputs, dogs and cats. this is not a function.

our third option is incorrect as well. the yellow square has two ouputs, the square and the triangle.

lastly, in our fourth option, we see the number 7 two times with a different output. therefore, this is not a function.

remember: each input must be paired with only one output!

1,150 give brainliest

step-by-step explanation

2r= 2300

r =1150