How many triangles are there in the given figure ?

21 22 20 19

21

The logic followed here is; (let's keep in mind the base, means how many triangles are there in the base) 1+2= 03  (AOB)  1+2= 03  (AMB) 1+2= 03  (ACM) 1+2= 03  (AOM) And, the other triangles are; COM, AOC, BOM, BMD, BCD, ACB, AOC, APC, CBM Therefore, there are 03+03+03+03+09= 21 triangles in the above figure.