To activate these data plans you would need to:
SMS 103 to 131 for 750MB costs N500
SMS 106 to 131 for
1.3GB 1.5GB costs N1000
SMS 110 to 131 for 3.5GB
3.75GB costs N2000
UPDATE: MTN has reviewed the amount of data offered, The 1.3GB plan got bumped up to 1.5GB, while the 3.75GB plan was reduced to 3.5GB.