Answer:
Metallic Balloons = 74
Bunches of Helium Balloons = 38
Explanation:
The question basically asks for the number of "metallic balloons" sold and the number of bunches of "helium balloons" sold.
We will do it in our way. Let B be number o metallic balloons and H be number of bunches of Helium balloons.
Since Metallics cost 2 each and Heliums cost 3.5 per bunch and totaled sales is 281, we can write and equation as:
2B + 3.5H = 281
and, since they sold 36 MORE metallic than helium ,we can write an equation as:
B - 36 = H
We can put 2nd equation in 1st one and solve for B first:

B = 74
Now, we find H:
H = B - 36
H = 74 - 36 = 38
H = 38