The logic for the formula you are looking for is in this format:
=if(logic test, true, false)
So, it would look like this:
cell a1 contains:
cell b1 contains:
=if(a1<49,"The value is less than 50","The Value is more than 50")
Cell b1 would now contain "The value is more than 50".
Please understand, you can nest logical if statements like so:
=if(logical test for test #1,if(logical test for #2,"true to test#2","false to test #2"),"false to test #1")
I hope this helps.