Question

Question 8

Which quantities in the previous question vary inversely with each other?
(a) x and y
(b) p and q
(c) r and s
(d) u and v

Answer 1

In option (b),
$\begin{array}{ccccc}p& 1^2& 2^2& 3^2& 4^2\\ q& 1^3& 2^3& 3^3& 4^3\end{array}$
If we multiply p and q with 1,2,3 and 4, we get the given result, But it is not given inversely.
In option (c),
$\begin{array}{cccccc}r& 2& 5& 10& 25& 50\\ s& 25& 10& 5& 2& 0.5\end{array}$
If we multiply r and s then all the results are same except 50 and 0.5, hence not an inverse variation
In option (d),
$\begin{array}{cccccc}u& 2& 4& 6& 9& 12\\ v& 18& 9& 6& 4& 3\end{array}$
If u =2, then v =18
If u =4, then v =9
If u =6, then v =6
If u =9, then v =4
and if u =12, then v =3
If show, when u increases, then v decreases.
Hence, it is inversely with each other.