Which number is closest to zero?

• A. 0.5
• B. 0.06
• C. 0.6
• D. 0.006

Answer: (D)

Being closest to zero means having the smallest distance from zero on the number line. For positive decimals, that distance is just the value itself—the smaller the value, the closer to zero it is.

Look at the options: 0.5 and 0.6 are in the tenths place, so they’re 0.5 and 0.6 away from zero—much farther than the others. The remaining numbers start with 0.0 in the tenths place, so they’re smaller. Between 0.06 and 0.006, 0.06 is six hundredths (0.06) and 0.006 is six thousandths (0.006). Since six thousandths is smaller than six hundredths, 0.006 is closer to zero than 0.06.

Therefore, the number closest to zero is 0.006.