1) 1 yard = 3 feet
2) 39 feet * [1 yard / 3 feet] = 13 yard
3) 13 yard * $ 4 / yard = $ 52
Answer: he will pay $ 52 for the fabric.
4) strip diagram
|-----| 1 yard = $4
|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----|
1 2 3 4 5 6 7 8 9 10 11 12 13
13 * 4 = 52 dollars