Answers to last issue's Brain Teasers

Ans 1. See the figure.

Ans 2. The four totals are eighteen, twenty, twenty four and twenty six.

One of the solutions that adds up to 18 is shown in the figure. The solution can be read row-wise as (6,1,7), (9,3,4,10), (8,2,5). The other possible solutions, reading row-wise from the top are 
(4,9,5), (7,1,2,8), (6,10,3) adding up to 20,
(9,6,2), (4,8,7,3), (1,5,10) adding up to 24, and
(5,10,4), (2,8,7,1), (3,9,6) adding up to 26.