the time it takes to mow the lawn at a large park m(x) varies inversley with the number of workers assigned to the job x . it takes 90 minutes to complete the job when 3 workers are assigned to it. which equation can be used to find the time to complete the job when x workers are assigned to it?
A.m(x)=270/x
B.m(x)=270x
C.m(x)=30/x
D.m(x)=30x

Question

the time it takes to mow the lawn at a large park m(x) varies inversley with the number of workers assigned to the job x . it takes 90 minutes to complete the job when 3 workers are assigned to it. which equation can be used to find the time to complete the job when x workers are assigned to it?
A.m(x)=270/x		
B.m(x)=270x
C.m(x)=30/x
D.m(x)=30x

tkhunny · Answer

Which produces 90 when x = 3?
Which is an inverse relationship?

.whitedragon. · Answer

im lost

tkhunny · Answer

Substitute x = 3 into each function.  Which ones give 90?  If it doesn't give m(2) = 90, then throw it out.

"Inversely Proportional" is a definition or description.  It means things go in opposite directions.  If you put in x = 4 (an increase), does m(x) increase of decrease?  If it ALSO increases, this is NOT "Inversely Proportional".  Throw it out.