Suppose that z varies jointly as u and v and inversely as w, and that z=.8 and when u=8, v=6, w=5. How do you find z when u=3, v=10 and w=5?

1 Answer
Sep 26, 2017

Answer:

#z=4/5#

Explanation:

#"the initial statement is "zprop(uv)/w#

#"to convert to an equation multiply by k the constant"#
#"of variation"#

#rArrz=(kuv)/w#

#"to find k use the given condition"#

#z=0.8" when "u=8,v=6,w=5#

#z=(kuv)/w#

#rArrk=(wz)/(uv)=(5xx0.8)/(3xx10)=0.8/6=8/60=2/15#

#"equation is " color(red)(bar(ul(|color(white)(2/2)color(black)(z=(2uv)/(15w))color(white)(2/2)|)))#

#"when "u=3,v=10" and "w=5#

#rArrz=(2xx3xx10)/(15xx5)=60/75=4/5#