The NORMAL OVERTIME RATE QRS 4.80 ( 4.80 /1.25 = 3.84 ( Basic rate )) 1.25 times of basic rate
THE FRIDAY RATE QRS 3.84 * 1.50 = QRS 5.76.

The monthly rate is confusing but the overtime and friday overtime rate is 1.25 times and 1.5 times respectively.

As per Qatar law - Normal overtime is 1.25 times of basic wage rate
Friday / Holiday overtime rate is 1.50 times of basic wage.

Hope you understood.