9709 P61 - Jun 2025 - Q1 - 3 marks
9345
It is known that 1% of houses in a certain area have a wind turbine. A random sample of 400 houses in this area is chosen for a survey on domestic heating. The number of houses in the sample that have a wind turbine is denoted by \(X\).
Use a suitable approximating distribution to find \(\mathrm P(X\le3)\). [3]