Question

If y varies directly as x and z, and Y=40 when x =5 andz = 4, find y when x=2 and z = 1

Pls answer it ASAP

Answer 1

Answer: When x=2 and z = 1, then the value of y =4.

Explanation:

Given: y varies directly as x and z i.e.
`y\ \alpha \ xz`

`y=k(xz)` (i) , where k is the proportionality constant.

Put Y=40 ,x =5 and z = 4, then we get

`40=k(5*4)\\\\\Rightarrow\ k=(40)/(20)\\\\\Rightarrow\ k=2`

Required equation:
`y=2(xz)` [Put value of k in (i)]

Now put x=2 and z = 1, then we get

`y=2(2*1)=2(2)=4\\\\\Rightarrow\ y=4`

Hence, when x=2 and z = 1, then the value of y =4.