a. 10 yd.×3 yd.=30 square yards;
b. 15 ft.×18 ft.=279 square feets;
c. 13 yd.=13×3 ft.=39 ft.=39×12 in.=468 in., 2 ft. 6 in.=2×12+6 in.=30 in., then 13 yd. 2 ft. 6 in.×15=498 in. × 15=7470 in.;
d. 198 sq. yd.=198 ×9 sq. ft.=1782 sq. ft.
198 sq. yd. 8 sq. ft. =1782+8 sq. ft.=1790 sq. ft.
Then 1790 sq. ft. × 7=12530 sq. ft.
