Final answer:
To find what decimal number describes 10% of 0.04, we multiply 0.04 by 0.10 and get 0.004, which means that option A is the correct answer.
Step-by-step explanation:
To find what decimal number describes 10% of 0.04, we start by understanding that 10% can be expressed as the decimal 0.10 (since 10% is the same as 10/100, which simplifies to 1/10, or 0.10). To calculate 10% of any number, you multiply the number by 0.10. Applying that here:
10% of 0.04 = 0.04 × 0.10 = 0.004
This calculation moves the decimal point one place to the left. When multiplying by powers of 10, moving the decimal place to the right increases the value, while moving it to the left decreases the value. If we were to move the decimal two places to the right (multiplying by 100), we would get 4, which means when we move it one place to the left (multiplying by 0.10), we properly calculate 10% as 0.004. Answer option A is correct.