It's likely that your tile is 12 x 12 inches and 70 of them would cover 70 square feet. If in fact your tile is 12 x 12 feet, one of them would be more than twice the size of the available area.
630 square feet.
70 x 10 = 700 square feet.
14 feet x 70 feet = 980 square feet.
840 square feet.
7 * 10 = 70 square feet.
70 square meters = ~753.5 (753.473729) square feet.
14 × 5 = 70 square feet.
630 square feet.
70 x 10 = 700 square feet.
70 square meters = 753.473 square feet.
14 feet x 70 feet = 980 square feet.
840 square feet.
The answer is 70 560 square feet.
70 square feet on the ceiling, and another 70 square feet on the floor. We don't know how many square feet on the walls unles we know the height of the ceiling.
70 square meters = 753.47 square feet
Total square feet: 21,000.0
70 x 24 = 1,680 square feet.