Posted by Daeun on Monday, March 15, 2010 at 8:46pm.
a triangle b means (10*a) + b. for an example,5 triangles 4= (10*5)=50+4 =54.find the value of8 triangle 1.

math  an, Monday, March 15, 2010 at 9:04pm
(10 * 8) + 1 =
80 + 1
= 81
After your examples I am sure you could have figured this one out