I am sure someone can assist with this basic formula question but I am unable
to get it to work correctly.

I want to create a formula that will reference another sheet to do the
following:
Sheet 2
A1 = 210 B1=211.045645
A2 = 211 B2=212.098332
A3 = 212 B3=213.123123

Sheet 1
C1=210

Sheet D1 formula - (if value of c1 is < sheet 2 B1 return value in sheet2
A1)(if value is B1 but <b2 = A2 and so on and so forth) I want this formula
to continue looking up for the B value that is closest to my # in question
and return the value in the adjacent A column. I have approximately 250
individual comparison fields to look up so I am hoping to have a formula that
will accomplish this without being too cumbersome.

I appreciate it!!!