regarding output voltage of INA125

load cell ina125 has output voltage 0 to 2.7 at loading max.10kg having Rg=300 ohms.I want to increase output voltage of ina125 0 to 5 volt.So how can i achieve this?

By using a non inverting operational amplifier with a gain of 5/2.7

The INA125 is not a rail2rail instrumentation opamp.
You need a higher supply voltage (>7volt) if you want 5volt out.
You also need that higher supply voltage if you want a stable 5volt (or 10volt) excitation for your load cell.
Then you're still stuck with the low resolution of Arduino's 10-bit A/D.
Dump the INA125, and move to a digital HX711 breakout board.