A student compared and –0.3. He changed to the decimal –0.25 and wrote, “Since 0.3 is greater than 0.25, –0.3 is greater than –0.25”. What was the student’s error?

As we can see that

0.3 value is greater than 0.25

∵ They are positive values

As we move to negative numeral system

Negative sign makes value smaller

Moving from 0 to -∞ we gets decreasing order of values

∴ more the value to the negative sign less it counts

And less the value to negative sign more it counts

As 0.3 value is greater than 0.25

But due to negative sign

-0.3 gets smaller than -0.25

∴ Student error was –0.3 is greater than –0.25

Instead he has to write –0.3 is smaller than –0.25