They both pay into the total of $950. Whatever they pay must add up to $950. Judy's share + Lynn's share= $950.

Okay what do we know about Judy or Lynn's share?

The problem said:

> Her (Lynn) share of the cost is $250 less than twice Judy’s.

Okay so what is Judy's share? We don't actually know. So let's call it the variable x. But what we do know is that Lynn's share is described in terms of Judy's and that is above. So Lynn's share is 2x-250 and as I already said Judy's is just x. Remember they must sum to $950. Make an equation and solve.