1. If y varies directly as x, and y=8 when x=4. Find y when x=10, the constant of variation and the equation of variation.
2. If y varies directly as x, and y= 0.9 when x= 0.3. Find y when x= 1.5, the constant of variation and the equation of variation.
3. If y varies inversely as, and y= 10 when x=1/2. Find x when y= 3, the constant of variation and the equation of variation.
4. If v varies jointly as w and u, and v=14 when w=7 and u=13. Find v when w=3/4 and u=6, the constant of variation and the equation of variation.
5. If m varies directly as n and inversely as p and m=9 when n=2 and p=1/3. Find m when n=1/2 and =1/3, the constant of variation and the equation of variation.