  We introduce operational quantum tasks based on betting with risk-aversion --
or quantum betting tasks for short -- inspired by standard quantum state
discrimination and classical horse betting with risk-aversion and side
information. In particular, we introduce the operational tasks of quantum state
betting (QSB), noisy quantum state betting (nQSB), and quantum channel betting
(QCB) played by gamblers with different risk tendencies. We prove that the
advantage that informative measurements (non-constant channels) provide in QSB
(nQSB) is exactly characterised by Arimoto's $\alpha$-mutual information, with
the order $\alpha$ determining the risk aversion of the gambler. More
generally, we show that Arimoto-type information-theoretic quantities
characterise the advantage that resourceful objects offer at playing quantum
betting tasks when compared to resourceless objects, for general quantum
resource theories (QRTs) of measurements, channels, states, and
state-measurement pairs, with arbitrary resources. In limiting cases, we show
that QSB (QCB) recovers the known tasks of quantum state (channel)
discrimination when $\alpha \rightarrow \infty$, and quantum state (channel)
exclusion when $\alpha \rightarrow -\infty$. Inspired by these connections, we
also introduce new quantum R\'enyi divergences for measurements, and derive a
new family of resource monotones for the QRT of measurement informativeness.
This family of resource monotones recovers in the same limiting cases as above,
the generalised robustness and the weight of informativeness. Altogether, these
results establish a broad and continuous family of four-way correspondences
between operational tasks, mutual information measures, quantum R\'enyi
divergences, and resource monotones, that can be seen to generalise two
limiting correspondences that were recently discovered for the QRT of
measurement informativeness.
