There must be 67 marbles.
17
The fifth line will have 19 marbles. 4 5 7 11 19
18
the answer is 4
There must be 67 marbles.
22 marbles are in the fifth line.
Oh honey, let me break it down for you. If the first line starts with 10 marbles, and each consecutive line has one less marble than the previous line, by the time you get to the seventh line, you'll have 4 marbles. So, grab those 4 marbles and go win that game, darling!
33 marbles must be in the sixth line
17
36
The fifth line will have 19 marbles. 4 5 7 11 19
1
18
36
10
the answer is 4