& \mathbf{Describe:} && \text{There are}\ 8\ \text{bananas in a box weighing a total of}\ 3.2\ \text{pounds. A sign shows that}\\& && 4\ \text{pounds of bananas cost}\ \$2.00. \\\\& \mathbf{My \ Job:} && \text{Figure out the cost of one banana. Assume bananas weigh the same.} \\\\& \mathbf{Plan:} && \text{Use a proportion to figure out the cost of}\ 3.2\ \text{pounds of bananas}. \\ & && \text{Then divide that cost by 8 to get the cost of one banana}. \\\\& \mathbf{Solve:} && \frac{4\ pounds}{\$ 2.00} = \frac{3.2\ pounds}{x \ dollars}; 4x = \$2.00 \times 3.2.\ \text{So},\ 4x = \$6.40,\ \text{and}\ \$6.40 \div 4 =  \$1.60. \\& && \text{One banana costs}\ \$1.60 \div 8,\ \text{or}\ \$0.20. \\\\& \mathbf{Check:} && \text{One banana weighs}\ 3.2 \div 8,\ \text{or}\ 0.4\ \text{pounds and costs}\ \$0.20. \\& && 10\ \text{bananas} \times 0.4\ \text{pounds/banana} = 4\ \text{pounds}. \\& && 10\ \text{bananas} \times \$0.20/\text{banana} = \$2.00