Bogani makes 3-legged stools and 4-legged chairs.

Question

Bogani makes 3-legged stools and 4-legged chairs. Last month he used 72 legs altogether. He made 3 more stools than chairs. How many stools and how many chairs did he make?

Answer 1

Hi Melissa, let x represent the 3-legged stool and y represent the 4-legged stool.

 

First equation:

 

3x + 4y = 72, because the question gives the number of legs used and not the number of stools. Therefore, each x must be multiplied by 3 and each y must be multiplied by 4.

 

Second equation:

 

x = y + 3, because there were 3 more 3-legged stools made than 4-legged stools.

 

Substitute for x in the first equation:

 

3(y + 3) + 4y = 72

 

3y + 9 + 4y = 72

 

7y + 9 = 72

 

Subtract 9 to both sides:

 

7y = 63

 

Divide both sides by 7:

 

y = 9

 

Substitute for y in the second equation to find x:

 

x = 9 + 3, or x = 12.

 

Bogani  made 12 3-legged stools and 9 4-legged stools.

 

Questions?