IF statement assistance required

Hi, I been trying to work out the best way to get excel calculate for me, I really need you guys help!

My problem is this:-

How do I get excel to calculate for me:

Between 6.000 to 6.049 is 6.7
Between 6.050 to 6.099 is 6.75
Between 6.100 to 6.149 is 6.8

and so on..


lets say i put 5.94, how do i get excel to find and calculate for me.. the answer should be 6.60.

Can you please teach me the formula to input?

Basically Between difference is 0.049, and each 0.049 difference is 0.05 difference