Pens             Pencils              Total

John                  2u                  u                         3u    (pencils John bought was 1/2 of  pens he bought)

Jimmy              3p                  2p                       5p    (Jimmy bought 2/3 as many pencils as pens)

3u = 3(5p) = 15p     (John bought thrice as many pens and pencils as Jimmy)

u = 5p

                           <——————————- Pen  ————————————–><———Pencil——————->     

John                 [                     u                       ][                     u                       ][                     u                       ]

                          [                    5p                      ][                  5p                       ][                     5p                      ]

Jimmy             [       3p               ][      2p        ]

                          <——Pen——-><—Pencil–>

Hence ratio of John’s pens to Jimmy’s pens =  10p : 3p  = 10 : 3

Thank you (:

If John bought U pencils, then he bought 2U pens.

If Jimmy bought 2P pencils, then he bought 3P pens.

Given  John bought total 3 times total of Jimmy,

3*(2P+3P)= U+2U

15P=3U

U=5P

John pen to Jimmy pen ratio = 2U/3P = 10P/3P = 10/3 or the ratio is 10: 3

Thank you (:

Lol.  This looks suspiciously to be “algebra” to me… 🙂

Thank you for the good solution.