Word Problems Practice Test
Quizsummary
0 of 5 questions completed
Questions:
 1
 2
 3
 4
 5
Information
Time Limit: 10 min
You have already completed the quiz before. Hence you can not start it again.
Quiz is loading...
You must sign in or sign up to start the quiz.
You have to finish following quiz, to start this quiz:
Results
0 of 5 questions answered correctly
Your time:
Time has elapsed
You have reached 0 of 0 points, (0)
Average score 

Your score 

Categories
 Word Problems 0%
 1
 2
 3
 4
 5
 Answered
 Review

Question 1 of 5
1. Question
Marie has 25 ounces of a 20% boric acid solution which she wishes to dilute to a 10% solution. How much water does she have to add to obtain a 10% solution?
Correct
Let X = Number of Ounces of 0 percent solution
0.2*25 = 0.1(X + 25)
⇒ 20*25 = 10(X + 25)
⇒ 500 = 10X + 250⇒ 10X = 250
⇒ X = 25 OuncesIncorrect
Let X = Number of Ounces of 0 percent solution
0.2*25 = 0.1(X + 25)
⇒ 20*25 = 10(X + 25)
⇒ 500 = 10X + 250⇒ 10X = 250
⇒ X = 25 Ounces 
Question 2 of 5
2. Question
How much pure alcohol must a nurse add to 10 liters of 60% alcohol to strengthen it to a 90% solution?
Correct
Let X = Number of Liters of 100 percent solution
X + 0.6*10 = 0.9(X + 10)
⇒ 100X + 60*10 = 90(X + 10)
⇒ 100X + 600 = 90X + 900
⇒ 10X = 300
⇒ X = 30 LitersIncorrect
Let X = Number of Liters of 100 percent solution
X + 0.6*10 = 0.9(X + 10)
⇒ 100X + 60*10 = 90(X + 10)
⇒ 100X + 600 = 90X + 900
⇒ 10X = 300
⇒ X = 30 Liters 
Question 3 of 5
3. Question
A store wants to mix two grades of coffee. One sells for $.80 per pound and one sells for $1.20 per pound. He wants to sell the mixture for $1.10 per pound. If he has 25 pounds of the $.80 per pound coffee, how much of the $1.20 must he use.
Correct
Let Y = Pounds at $1.2
Using 25 Pounds of $ 0.8 ingredient
Must make a mixture costing $ 1.1 per Pounds
Resulting mixture is to be 25 + Y Pounds
1.2 Y + 0.8 * 25 = 1.1(25 + Y)
⇒ 1.2 Y + 20 = 27.5 + 1.1 Y
⇒ 7.5 = 0.1 Y
⇒ Y = 75 PoundsIncorrect
Let Y = Pounds at $1.2
Using 25 Pounds of $ 0.8 ingredient
Must make a mixture costing $ 1.1 per Pounds
Resulting mixture is to be 25 + Y Pounds
1.2 Y + 0.8 * 25 = 1.1(25 + Y)
⇒ 1.2 Y + 20 = 27.5 + 1.1 Y
⇒ 7.5 = 0.1 Y
⇒ Y = 75 Pounds 
Question 4 of 5
4. Question
A farmer wants to mix milk containing 3% buttermilk with cream containing 30% butterfat to obtain 900 gallons of milk which is 8% butterfat. How much of each must he use?
Correct
Let X = Gallons of 30 percent ingredient
Let Y = Gallons of 3 percent ingredient
Find X and Y to obtain a 900 Gallons mixture of 8 percent
X + Y = 900
⇒Y = 900 – X30X + 3Y = 8*900
⇒30X + 3(900 – X) = 7200
⇒30X + 3*900 – 3X = 7200
⇒27X = 7200 – 2700
⇒X = 166.667 GallonsY = 900 – 166.667
⇒Y = 733.333 GallonsIncorrect
Let X = Gallons of 30 percent ingredient
Let Y = Gallons of 3 percent ingredient
Find X and Y to obtain a 900 Gallons mixture of 8 percent
X + Y = 900
⇒Y = 900 – X30X + 3Y = 8*900
⇒30X + 3(900 – X) = 7200
⇒30X + 3*900 – 3X = 7200
⇒27X = 7200 – 2700
⇒X = 166.667 GallonsY = 900 – 166.667
⇒Y = 733.333 Gallons 
Question 5 of 5
5. Question
In a school of 320 students, 85 students are in the band, 200 students are on sports teams, and 60 students participate in both activities. How many students are involved in either band or sports?
Correct
Incorrect