Question

• A. 24
• B. 21
• C. 19
• D. 9

Answer 1

Answer:

B. 21

There are 21 triangles in the given figure.

When lines are drawn from the top apex of a triangle to its base, you can find the total number of triangles by numbering the individual small compartments at the base and adding them up:

1. Number the base compartments from left to right: 1, 2, 3, 4, 5, 6.

2. Add these numbers together:
   $\text{Total Triangles} = 1 + 2 + 3 + 4 + 5 + 6 = \mathbf{21}$

Alternatively, using the formula:

$\text{Total Triangles} = \frac{n(n + 1)}{2}$
Where $n = 6$ (the number of compartments):
$\text{Total Triangles} = \frac{6 \times 7}{2} = \mathbf{21}$