40 is no more significant than other numbers, and considerably less so than numbers such as π or e.
37.753 rounded to one significant figure becomes 40
40
Rounded to one significant figure it becomes 40
40
39 remains 39 when rounded to one significant figure.
4
10080 has 5 significant figures - so 1 significant figure would be: 10000.
849 to 1 significant figure is 800. This is because the first non-zero digit is 8, so the significant figure is the hundreds place.
The number 02 has one significant figure because a leading zero is not significant. So the significant figure is the digit 2.
To one significant digit, 37.19 is 4x101. Writing it as 40 makes it unclear as to whether you have 1 significant digit or 2.
Left zero's are NOT significant: So it's one in 0.01
Well to figure out what the least common factor for 36 and 40 is to figure out the multiples for 36 and 40. Then figure a multiple that both 36 and 40 have the least value. I know you probably don't care of what I just typed so here's the answer. The LCM for 36 and 40 is 1.