Short answers, pulled from the story.
National Numeracy defines numeracy as the ability to understand how mathematics is used in the real world to make the best possible decisions. This skill involves thinking and reasoning just as much as doing sums.
Humans have evolved two major systems for mental number representation that are often thought to be innate and shared across cultures. One system allows for an approximate representation of numerical magnitude while the second demonstrates precise representation of the quantity of individual items.
Socioeconomic status plays a key role because children brought up in families with high socioeconomic status tend to be more engaged in developmentally enhancing activities. A mother's education level has a significant effect on the child's ability to achieve in numeracy, with higher education levels correlating with greater success.
Many professions require individuals to have well-developed numerical skills including mathematician, physicist, accountant, actuary, financial analyst, engineer, and architect. Carpenters and interior designers also need to measure, use fractions, and handle budgets effectively.
Health numeracy is defined as the degree to which individuals have the capacity to access, process, interpret, communicate, and act on numerical health information needed to make effective health decisions. Patients who lack these skills run the risk of making poor health-related decisions due to an inaccurate perception of information.