To get the correct answer, try different options and see what happens. Use estimation to limit the number of problems you solve.Evan and Natalie: 34+15=1520+420=19201920 is less than 1. This is not enough.Natalie has more sand than Min. Combining Evan's sand and Natalie's sand was not enough, so combining Evan's sand and Min's sand will not be enough, because it will be even less.Both Natalie and Min have less than 12 pound of sand, so together, they cannot have more than 1 pound.Try adding all three amounts.34+15+18=3040+840+540=4340=13401340 is greater than 1. Sarah gets enough sand when she takes sand from all three of her friends.