BBC Capital published this post, Why it matters if we become innumerate. The article says:

“What we all need in daily life is quite simple maths,” says Mike Ellicock, chief executive of the charity National Numeracy. “But we also need a conceptual understanding applied to complex situations.” In essence, this understanding applies to a broad range of mathematical information that may be intricate, abstract, or embedded in unfamiliar contexts.

For instance, you might need to calculate the true cost of buying versus hiring a car; whether to use award points or money to buy an airline ticket; or how to adjust a recipe to feed six people instead of four.

In the first two examples, you deal with businesses which are not much interested in you being numerate. I have already said on a number of occasions that

If banks and insurance companies were interested in having numerate customers – as they occasionally claim – we would witness the golden age of school mathematics: fully funded, enjoying cross-party political support, promoted and popularised by the best advertising companies in all forms of mass and social media. But they are not; banks and insurance companies need numerate workforce – but even more so they need innumerate customers. 25 years ago in the West, the benchmark of arithmetic competence at a consumer level was the ability to balance a chequebook. Nowadays, bank customers can instantly get full information about the state of their accounts from an app on a mobile phone together with a timely and tailored to individual circumstances advice on the range of recommended financial products. This kind service can be described in a logically equivalent form: a bank can instantly exploit the customer’s vulnerability.

Growing innumeracy is a quite alarming socio-economic phenomenon, and it has very deep roots. Read mor on that in my papers:

Mathematics for makers and mathematics for users, bit.ly/2qYHtst

Calling a spade a spade: Mathematics in the new pattern of division of labour, goo.gl/TT6ncO