The average age of 3 girls is 40 years and their ages are in the proportion 1:2:3. The age of the youngest girl is?
Choose the correct choice from the following answers:
A) 22 years	B) 23 years	C) 21 years	D) 20 years	E) 25 years
Total age of 3 boys = 40*3= 
<gadget id="calculator">40*3</gadget>
<output>120</output>
120   ratio of their ages= 1:2:3   Age of the youngest =120*1/6= 
<gadget id="calculator">120*1/6</gadget>
<output>20</output>
20 years   Answer is 20 years
<result>D</result>
The average age of 3 girls is 40 years and their ages are in the proportion 1:2:3. The age of the youngest girl is?