Question

Fertilizer is sold in bags labeled with three numbers that indicate the amount of nitrogen (N), phosphoric acid (P2O5), and potash (K2O) present.

A bag of Vigoro Ultra Turf has the numbers "29−3−4," which means that 100 pounds of this fertilizer contains 29 pounds of nitrogen, 3 pounds of phosphoric acid, and 4 pounds of potash.
A bag of Parker's Premium Starter has 18 pounds of nitrogen, 25 pounds of phosphoric acid, and 6 pounds of potash per 100 pounds. (See the discussion at the start of the section.)

Determine the total amount of nitrogen, phosphoric acid, and potash in the given mixture. 100 pounds of Vigoro, 400 pounds of Parker's.

Answer 1

Nitrogen: 101 pounds

Phosphoric Acid: 103 pounds

Potash: 28 pounds

Explanation:

Hi,

We need to find out the total amount of all three compounds.

We first start with 100 pounds of Vigoro Ultra Turf, (this information can simply be determined from the question):

Nitrogen: 29 pounds

Phosphoric Acid: 3 pound

Potash: 4 pound

Next we check for Parkers' Premium Starter. In 100 pound of this bag, we get:

Nitrogen: 18 pounds

Phosphoric Acid: 25 pounds

Potash: 6 pound

But we need to calculate for 400 pounds of Parker's:

Nitrogen:
`(18)/(100)` × 400 = 72 pounds

Phosphoric Acid:
`(25)/(100)` × 400 = 100 pounds

Potash:
`(6)/(100)` × 400 = 24 pounds

We add amounts from both bags to find the total:

Nitrogen: 29 + 72 = 101 pounds

Phosphoric Acid: 3 + 100 = 103 pounds

Potash: 4 + 24 = 28 pounds