60x60=3600 sq inches of fabric, minimum. 3600/40In wide =90 liniar in = 2.5 yd minimum. If the same proportions as each block are given to the fabrics you'd need 3/4 yd background, and 3/8 of each of the 5 colors. I'd increase it to 1 yd background and 1/2 yd of each of the 5 colors. Cut it out immediately to see if that was enough so you can go back to the store for more.