The question does not provide units of measure which are important in answering the question. However, it is likely that the slab is 1400 square feet and that the slab thickness is 3 inches. A cubic yard of concrete is 3 ft by 3 ft by 3 ft, or 27 cubic feet.
To solve the problem, you convert the slab size into cubic feet by multiplying the length in feet by the width in feet (to get 1400 square feet) by the thickness of the slab in inches divided by 12 inches per foot or 1400 * 3 / 12 = 350 cubic feet.
To convert to cubic yards, divide the 350 cubic feet by 27 cubic ft/cubic yard to get 12.96 cubic yards. So, order 13 yards of concrete.
You will need a minimum of 7.41 cubic yards.
Need to know how many bags of cement I will need for a 20x10 space?
2.2 Yards
100
There are not enough measurements to calculate square yards. It would need to be 7500 by (another measurement) to calculate.
You will need 6.17 cubic yards of cement.
8.64 cubic yards of cement.
You will need a minimum of 7.41 cubic yards.
12.96 yards
At 8" thick, you will need at least 4.67 cubic yards.
You will need a minimum of 7.41 cubic yards.
You will need 27.6 cubic yards of cement.
You will need a minimum of 18.96 cubic yards.
13*13*6=1014 yards of cement
For this area you will need 2.4 cubic yards.
56'x46'x4" requires 31.8 cubic yards.
You will need a minimum of 3.56 cubic yards.