800
400 x 19 = 7600
400 multiplied by 500 is 200,000.
20 X 20 = 400.
500 multiplied by 400 is 200,000.
2 and 5. You will need to multiply 2 four times and 5 twice.
One-and-a-half times 400
40
400 x 2 = 800
400 * 200 = 400 * 100 * 2 = (400 * 100) * 2 = 40000 * 2 = 80000
Let 4x = 400. x = 400/4 =100. Therefore 4 * 100 = 400
400 x 10^3 is equal to 400,000.
It is a square number because 20 times 20 = 400