Question

36 workers I need 1 pen for each worker. For every 3 people who prefer red pens,there are 9 who prefer blue. How many blue pens do I need

Answer 1

r = number of red pens
b = number of blue pens

If we have 36 workers and each worker requires a pen, we need 36 pens.

36 = r + b
3r = b (For every 3 red there are 9 blue. So there are 3 times as many blue as red)

Now, substitute 3r = b into the first equation.

36 = r + b = r + 3r = 4r
36 = 4r
9 = r

Therefore, we need 9 red pens. Plug this back into our 3r=b equation to solve for b.

3r = b
3(9) = b
27 = b

Therefore, we need 27 blue pens.

Answer 2

blue 9 x 3 = 27
red 3 x 3 = 9
27 + 9 = 36
I hope this helps