Adding an element to each list (in a list) in Scheme/Racket?

Question

I just starting learning functional programming and need help with something that I would think is really easy, but can't figure out (been a long day).

Basically I have multiple lists (each with ints) within a bigger list. I want to add an element to each list. What I have so far, but can't finish off...

(define (number-adder lstInlst x)
     (map append x somehow??? lstInlst))

Any help is appreciated!

Answer 1

(map (lambda (lst)
       (cons x lst))
     list-of-lists)

Since you're using Racket, you can use curry for something even shorter:

(map (curry cons x) list-of-lists)