"Hand-reflexology work provides a simple formula: just as the bank takes our deposits and holds them ready for our use, hand-reflexology techniques contribute to our bank of 'wellness standing'."
What does "formula" mean in this context?
Formula 1 > money + bank [savings] account = money in reserve = money available for use
Formula 2 > manipulation of the hand+personal attention = improved flexibility and mobility = a feeling of being healthy
I believe Angelika you wanted to explain the word mathmatically/formally.
1. Formula as a countable noun (as used in the poster's text) is a standard or accepted way of doing or making something, or is a mathematical rule expressed in a set of numbers and letters. Develop all the details of a plan for doing something:
There's no magic formula for success.
2. Formula as an uncountable noun is artificial milk which can be given to babies instead of milk from their mother.