pressing ‘u, I, O, J…’ letters on the right side of keyboard, numbers come up instead.why?

When you press the ‘U, I, O, J, K, L…’ letter keys on the right side of keyboard, occasionally numbers may come up instead. This situation usually occurs when Num Lock has been enabled.

To solve this problem, you should turn Num Lock off. To disable Num Lock, press the FN key and F11.

NOTE:   Some old models have their own Num Lock keys marked as “Num Lock”

Some models have status indicators. When the Num Lock key is pressed (activated,) the Num Lock light turns on. Please refer to the image below.

NOTE : It is not applicable to the models which have numeric keypads (Example: R610, R710, R720)