Question

1. A quantity is partly constant and partly varies inversely as the square of x.write the relationship between x and y when x=1,y=11 and when x=2,y=5.find the values of y when x=4. 2.find,correct to the nearest naira,the compound interest on 85750 naira for 3 years at 5%per annum.

Answer 1

y = a + b/x^2
So, using the two given points,
a + b = 11
a + b/4 = 5
Now find y when x=4

85750(1.05^3 - 1)