so percent means parts out of 100 so
4%=4/100=0.04
inflation is increase in cost
1=100%
100%+4%=1+0.04=1.04
so 1 year from now, the blender will cost 47+(47 times 0.04)=47 times 1.04
next year it will be (47 times 1.04) times 1.04
next year it will be ((47+(47 times 1.04) times 1.04) times 1.04
the answer is it will cost $52.87