Uhh I guess so? I've never seen that before in any service manual.
Pick a number. It's quite difficult to torque ***exactly***, esp if you are using a click type wrench. They usually good for +-20%.
If you needed much more accuracy, it would specify to use say a needle type or more accurate digital gauge.
Set the wrench to 20. You'll be fine.
Actually, I haven't used a cheaper manual like a Haynes / Chilton in a looong time, but do they specify ranges like that?
what you using to torque?
you need a small inch pound wrench for your intake manifold. even if your wrench has a scale that does down to 10-20 ft lbs, it's not going to be accurate at that low reading, and your bolts may break (or the intake will crack).
personally i never recommend torqing anything except mains, rods, head bolts, and maybe a few other select fasteners. intake or timing cover bolts, no. but if you must, make sure you have the right wrench for the job.