The balloons were released to celebrate National Numbers Day last Friday at Widney Junior School and one was found the next day in Sprakensehl, Germany.
Timo Schrader, seven, found the deflated balloon and question tag at the bottom of his driveway and returned it with the answer, 27.
The question was: “I am thinking of a number, double it and add 40. The answer is 94. What was the number I was thinking of?”
Anyone who finds a balloon can send answers to Chapel Fields Training Centre, Richmond Road, Solihull or email cfcadmin@solihull.gov.uk by Wednesday December 16.
Information provided by Solihull Metropolitan Borough Council.
