ALA PreAlgebra Unit 4 Ratios and Proportions Unit
ALA: Pre-Algebra Unit 4 Ratios and Proportions Unit 4 Review Flashcards
Simplify:
3: 18
1: 6 X + X
4: 1
1: 3
Determine the number that will make this statement a true proportion: 16: 14 = 8: ?
16: 14 = 8: 7
A hospital shift has 6 nurses and 2 doctors on duty. What is the ratio of nurses to doctors? Simplify if possible.
The ratio of nurses to doctors is 6: 2, which simplifies to 3: 1 X + X
A hospital shift has 6 nurses and 2 doctors on duty. What is the ratio of doctors to nurses? Simplify if possible.
The ratio of doctors to nurses is 2: 6, which simplifies to 1: 3 X + X
A hospital shift has 6 nurses and 2 doctors on duty. What is the ratio of nurses to total medical personnel? Simplify if possible.
The ratio of nurses to total medical personnel is 6: 8, which simplifies to 3: 4 X + X
A hospital shift has 6 nurses and 2 doctors on duty. What is the ratio of doctors to total medical personnel? Simplify if possible.
The ratio of doctors to total medical personnel is 2: 8, which simplifies to 1: 4 X + X
A hospital shift normally has 6 nurses and 2 doctors on duty. To prepare for an oncoming storm, the hospital will have 4 doctors on duty. How many nurses should be on duty to keep the usual ratio?
If we double the number of doctors, we need to double the number of nurses, so 12 nurses will be on duty. X + X We could also set up a proportion: 2 doctors = 4 doctors 6 nurses x nurses 2 x = 24, so x = 12 nurses
A hospital shift normally has 6 nurses and 2 doctors on duty. To prepare for an oncoming storm, the hospital will have 3 doctors on duty. How many nurses should be on duty to keep the usual ratio?
We could set up a proportion: X + X 2 doctors = 3 doctors 6 nurses x nurses 2 x = 18, so x = 9 nurses
A hospital shift normally has 6 nurses and 2 doctors on duty. To prepare for an oncoming storm, the hospital will have 15 nurses on duty. How many doctors should be on duty to keep the usual ratio?
We could set up a proportion: X + X 2 doctors = x doctors 6 nurses 15 nurses 6 x = 30, so x = 5 doctors
Is this a true proportion? 12 = 20 15 40
X + X No, since 12 x 40 is not equal to 15 x 20.
Is this a true proportion? 5 = 20 15 60
X + X YES, since 5 x 60 Is equal to 15 x 20.
It takes 8 hours to drive 120 miles. How long will it take to drive 60 miles?
If we drive half as many miles, it will take half as long, so it will take 4 hours. X + X We could also set up a proportion: 120 miles = 60 miles 8 hours x hours 120 x = 480, so x = 4 hours
2 out of 5 people prefer Coke to Pepsi. In a crowd of 300 people, how many would you expect to prefer Coke?
We could set up a proportion: X + X 2 Coke = x Coke 5 people 300 people 5 x = 600, so x = 120 Coke-lovers
2 out of 5 people prefer Coke to Pepsi. In a crowd of 300 people, how many would you expect to prefer Pepsi?
We could set up a proportion: 3 Pepsi = x Pepsi 5 people 300 people X + X 5 x = 900, so x = 180 Pepsi-lovers (We could also have subtracted 300 – 120 from the previous problem!)
You are done with the ALA Unit 4 Review
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