Answer:
To multiply 0.12 x 0.4, first you need to write the numbers in standard form. 0.12 can be written as 0.120 and 0.4 can be written as 0.400.
Then, multiply the numbers by first multiplying the digits in the ones column, then the digits in the tenths column and finally the digits in the hundredths column.
This is done by multiplying the first digit in the first number (1) with the first digit in the second number (4), then multiplying the second digit (2) with the second digit (0), and finally multiplying the third digit (0) with the third digit (0).
Therefore, the multiplication can be written as:
1 x 4 = 4 2 x 0 = 0 0 x 0 = 0
Adding these three numbers together gives us 0.048, which is the answer to 0.12 x 0.4.