If 13% of 100 is 13, than 13% of 100 million is 13 million. And multiplying two on both sides, we get that 13% of 200 million is 26 million. If we take it the other way, we get that 13% of 50 million is 6.5 million. As 6.5 million + 25 million is 31.5 million, this is our answer.