The answwer is 1, I think.
Use a proportion, in this case $${\frac{{\mathtt{x}}}{{\mathtt{6.87}}}} = {\frac{{\mathtt{20}}}{{\mathtt{100}}}} \Rightarrow {\mathtt{x}} = {\frac{{\mathtt{687}}}{{\mathtt{500}}}} \Rightarrow {\mathtt{x}} = {\mathtt{1.374}}$$
