Don L. answered • 12/31/15

Tutor

5
(12)
Fifteen years teaching and tutoring basic math skills and algebra

Hi Nicholas, the way to work these types of problems is to create a table. The table will have three rows and three columns.

The table:

Let x represent the kilograms of nuts, then 138 - x will represent the kilograms of bolts.

Product Amount Cost Total

--------------------------------------------------------

Nuts x .60 .60 * x

Bolts 138 - x .66 .66 * (138 - x)

Mix 138 .65 .65 * (138)

The equation:

The nuts plus the bolts must equal the mix or:

.60 * x + .66 * (138 - x) = .65 * 138

I do not like to work with decimals, so multiply each term by 100:

60 * x + 66 * (138 - x) = 65 * 138

Remove the parenthesis and combine like terms:

-6x = -66 * 138 + 65 * 138

-6x = -138

Divide both sides by -6:

x = 23

Solution:

The mixture contains 23 kilograms of nuts.

The mixture contains 138 - 23, or 115 kilograms of bolts.

Questions?