Express your answer using two significant figures.

Question

I have to express this by using two significant numbers, 18 ∘C , 185∘C , -45 ∘F

Answer 1

18ºC has 2 significant figures

185ºC has three significant figures. To express this with only 2 sig. figs., it would be 190ºC

-45ºF has 2 significant figures

If you are adding and subtracting (which isn't clear from the way the question is written), you'd have...

18C + 185C -7.22C = 195.78ºC = 2.0x10² ºC (2 sig. figs.)