Brainliest! 1) describe a situation where rounding numbers would be appropriate. 2) describe a situation where estimating would be appropriate.

1) rounding numbers (up) would be appropriate when in the store, trying to figure out if you have enough money for the item(s) you are attempting to purchase. 
2) estimating would be appropriate when trying to figure out an approximate time you will arrive at an event, or a measurement when cooking or distance. 

Best answer that i found on yahoo ok   set :   x= length of 2nd piece in cm  x- 3= length of 1st piece in cm  x-4= length of 3rd piece in cm  then since you know they all came from the 20 cm ribbon you add them together and set them equal to 20x+ x-3 +x-4 = 20  3x - 7= 20  3x= 27  x= 9  the shortest piece is the third piece which is x- 4  x-4  9-4 = 5  the length of the smallest piece is 5 cm.  the other lengths are  9 cm  6 cm