The waiting time in minutes, XXX, of a customer at a cafe is modelled by the probability density function
f(x)={kx(36−x2)0≤x≤60otherwise f(x) = \begin{cases} kx(36 - x^2) & 0 \le x \le 6 \\ 0 & \text{otherwise} \end{cases} f(x)={kx(36−x2)00≤x≤6otherwiseShow that k=1324k = \frac{1}{324}k=3241.
Using integration, find
the mean waiting time of a customer,
the probability that a customer will wait for more than 4 minutes.
Three independent customers visit the cafe.
Find the probability that at least 2 of the customers wait for more than 4 minutes.
438 exam-style questions on OCR A Level Maths 1.8 Integration, covering 1.8.1 Fundamental theorem of calculus (A-level only), 1.8.2 Integrating x^n, 1.8.3 Integrating standard functions (A-level only), 1.8.4 Evaluating definite integrals, 1.8.5 Area between a curve and the x-axis, 1.8.6 Area between two curves, 1.8.7 Integration as the limit of a sum (A-level only), 1.8.8 Integration by substitution (A-level only), 1.8.9 Integration by parts (A-level only), 1.8.10 Use of partial fractions in integration (A-level only), 1.8.11 Differential equations with separable variables (A-level only), 1.8.12 Interpreting the solution of a differential equation (A-level only), and 1.8 Integration. Each one has a worked solution and a mark scheme showing where the marks go.