The second part of your post seems to be a different question than the first part... it seems that Haseeb has given you solution for the first part...

for second part (if a different question) try: =IF(LEFT(A1)="<","<"&MID(A1,2,10)*B1*8.34,ROUND(A1*B1*8.34,0))

this rounds the number to the next whole number if A1 contains only a number... but it will keep decimals if A1 starts with "<"