There is a bag that contains only red and blue marbles. The
probability of choosing a red
marble at random is 2/7.Given
that there are 12 red marbles in
total, and each one is likely to be
chosen at random work out out
how many marbles there must be
in total.

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.