Let x and y be the number of packs with 100 and 250 paper clips, respectively. The system of linear equations that would best represent the given is x + y = 84 100x + 250y = 12,300
The values of x and y from the equations are 58 and 26, respectively. If a person buys half of the packs of 250 paper clips, n = (0.5)(250)(26) = 3250
Metals are found in group 1, 2, and abit of 3. Non-metals are found in group 0/8, abit in 4, 5, 6 and 7 too. Here is a picture. Most of the periodic table are metals.