Need help around correct formulae nested if or index for attached query

[sui898]

I received test which i am not able to solve, Tried with nested if and logical function. I am beginner so if someone can help me out with correct answers. Thank you in advance photo_2021-12-10_23-34-07.jpg Tried nested if and function but as these are dynamic cannot make any logical query

[Bernie Deitrick]

Not sure what SLAB is - so don't know what you need.

But you use IFS incorrectly on the third sheet:

=IFS(B5<60,"F",B5>60<69,"D",B5>70<79,"C",B5>80<89,"B",B5>89,"A")

Should be:

=IFS(B5<60,"F",B5<70,"D",B5<80,"C",B5<90,"B",B5>=90,"A")

This type of condition: B5>60<69 is not valid. You can either have properly sorted conditions (the first true result kicks out the value) or change B5>60<69 to working logic, like AND(B5>=60,B5<=69)