twin brothers, person a and person b, can mow their grandparent's lawn together in 40 minutes. person a could mow the lawn by himself in 18 minutes less time than it would take person b. how long would it take person b to mow the lawn by himself?

Luke started a weight-loss program. the first week, he lost x pounds. the second week, he lost pounds less than times the pounds he lost the first week. the third week, he lost 1 pound more than of the pounds he lost the first week. liam started a weight-loss program when luke did. the first week, he lost 1 pound less than times the pounds luke lost the first week. the second week, he lost 4 pounds less than times the pounds luke lost the first week. the third week, he lost pound more than times the pounds luke lost the first week.