Question

the angles of a triangle are in the ratio 2 : 4 : 3. what is the measure of the smallest angle in the triangle?
a 60°
b 40°
c 80°
d 20°

Explanation:

Step1: Find the sum of ratio parts

$2 + 4+3=9$

Step2: Recall sum of triangle angles

The sum of interior - angles of a triangle is $180^{\circ}$.

Step3: Calculate the measure of one part

$\frac{180^{\circ}}{9}=20^{\circ}$

Step4: Find the smallest angle

The smallest ratio part is 2. So the smallest angle is $2\times20^{\circ}=40^{\circ}$

Answer:

B. $40^{\circ}$