Using Less/Greater Than operators for numbers within a range?

Hello all,

I am currently trying to organize some numerical data with formula operations, however I am having an issue Quickbase taking my code:

if([Units Inspected]=0,0,1<=[Units Inspected]<=4,1,5<=[Units Inspected],[Units Inspected]/4.5)

I need to be able to control the output values when the input values fall within the range of 1 and 4 (inclusive). However, Quickbase is marking the second <= in 1<=[Units Inspected]<=4 as not being able to apply the operator, thus not making any of the code work at all. (All outputs are blank)

Is there a way around this or a different operator that I can use to control values that fall within a stated range of values?

Any help is appreciated,

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Andrew Le
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