math question

Question

A solution is made by mixing 75.0 L of alcohol with 125 L of water. Find the percent concentration of alcohol in mixture.

How many litres of acid are there in 155 L of acid-water mixture that is 10.0% acid by volume?

Find the percent concentration of alcohol if 2.0 L of alcohol is added to 15 L of gasoline

 

Answer 1

Hi Haroon,

 

Let's begin with the 1st problem:

    % alcohol = ((75) / (75 + 125)) x 100

    % alcohol = (75/200) x 100

    % alcohol = (0.375) x 100

    % alcohol = 37.5

 

Next, we'll tackle the 2nd problem:

    # acid liters = 155 x 10%

    # acid liters = 155 x 0.10

    # acid liters = 15.5

 

Finally, we'll address the 3rd problem:

    % alcohol = (2 / (2 + 15)) x 100

    % alcohol = (2/17) x 100

    % alcohol = 0.1176 x 100

    % alcohol = 11.76

 

The concept to remember here is that a percent is a number representing the fraction part of 100:

    example:  fraction = 20/100; percent = 20

 

Thanks for submitting this problem and glad to help.

 

God bless, Jordan.