A person's website specializes in the sale of rare or unusual vegetable seeds. he sells packets of sweet-pepper seeds for $2.32 each and packets of hot-pepper seeds for $4.40 each. he also offers a 16-packet mixed pepper assortment combining packets of both types of seeds at $2.58 per packet. how many packets of each type of seed are in the assortment?

The first thing we must do in this case is to define variables.
 We have then:
 x = packets of sweet-pepper seeds
 16-x = packets of hot-pepper seeds
 We now write the equation to solve the problem:
 2.32x + 4.40 (16-x) = 2.58 (16)
 2.32x + 70.40-4.40x = 41.28
 -2.08x = -29.12
 x = (- 29.12) / (- 2.08)
 x = 14
 
 there are in the assortment:
 14 packets of sweet-pepper seeds
 16-14 = 2 packets of hot-pepper seeds