Two experiments measuring the population of insects are started at the same time. PA=ae0.2tP_A = ae^{0.2t}PA=ae0.2t and PB=be0.15tP_B = be^{0.15t}PB=be0.15t. At the start (t=0t=0t=0) total is 120. After 8 days (t=8t=8t=8) total is 480.
Show that a=50a = 50a=50, to the nearest whole number, and find the value of bbb.
Estimate the total number of insects after 10 days.
Find the day that the number of insects in experiment A exceed the number of insects in experiment B.
277 exam-style questions on Edexcel A Level Maths Exponentials and Logarithms, covering 14.1 Exponential Functions, 14.2 y = e^x, 14.3 Exponential Modelling, 14.4 Logarithms, 14.5 Laws of Logarithms, 14.6 Solving Equations using Logarithms, 14.7 Working with Natural Logarithms, and 14.8 Logarithms and Non-Linear Data. Each one has a worked solution and a mark scheme showing where the marks go.