use compatible whole numbers. Here is a word problem. Lindy had 14 pieces of string, if each piece of string was 3/8 of a inch about how many feet would be 14. First, you would round 14 to a compatible number (16) to 8 so 3/8 x 14~3/8 x 16.
Another way is...
To use a compatible benchmark fraction
Use a compatible benchmark fraction to estimate. Lindy had 14 pieces of string each 3/8 a foot and she wants do find out about how much a different way. 3/8 x 14~4/8 x 14= about 7 feet.