According to the theory of diminishing marginal utility, if a consumer is consuming additional units of a product and their marginal utility is positive but falling:
total utility is increasing at a decreasing rate.
total utility is maximised.
average utility must be negative.
total utility is decreasing.
45 exam-style questions on AQA A Level Economics 1.2 Individual economic decision making (A-level only), covering 1.2.1 Consumer behaviour, 1.2.2 Imperfect information, 1.2.3 Aspects of behavioural economic theory, and 1.2.4 Behavioural economics and economic policy. Each one has a worked solution and a mark scheme showing where the marks go.