184. A mixed packet of nuts contains 1 pound of walnuts and 2 pounds of Brazil nuts. It costs exactly $2. A packet containing 4 pounds of filberts and 1 pound of walnuts costs $3. And for only $1.50, you can buy a mixed packet of 3 pounds of almonds, 1 pound of walnuts, and 1 pound of filberts. How much should you pay for a mixture of 1 pound of each of the four kinds of nuts?
187. Two slow moving trains are traveling towards each other. One train runs from point A to point B at 19 miles an hour. The other train runs from point B to point A at 21 miles per hour. One hour before the trains pass each other, how far apart are they?