Amerchant blends tea that sells for $3.25 an ounce with tea that sells for $2.50 an ounce to produce 90 oz of a mixture that sells for $2.80 an ounce. how many ounces of each type of tea does the merchant use in the blend?

The amount of tea ounces that sells for $ 3.25 is 36, and the amount of tea ounces that sells for $ 2.50 is 54.

Step-by-step explanation:

We start by defining variables from the data provided:

a = amount of ounces of tea that sells for $ 3.25

b = amount of ounces of tea that sells for $ 2.50

c = amount of ounces of tea that sells for $ 2.80

From the problem we know that , and that . You can propose a system of equations:

Having the fact that c = 90, we can simplify the system:

Clearing a in the first equation we get:

And substituting in the second equation we arrive at:

Now we can use b in the first equation to get a:

We verify that , and that .

reduce the friction between its moving parts

step-by-step explanation:

in fact, by reducing the friction between the moving parts of the machine, it is possible to reduce the energy wasted due to this friction; therefore, more input energy is converted into useful work, and this will improve the efficiency of the machine.