Ratio Boxes and Proportions

A combination of processes

Ratios Boxes and Proportions

Ratio boxes are organizational tools.These same boxes can be extended to use for

problem solving with proportions.

This just presents another choice in problem-solving techniques.

The ratio of stalactites to stalagmites in the cavern was 9 to 5. If the total ofboth formations was 1260, how many stalagmites were in the cavern?

stalactites 9

stalagmites 5

total 14 1260

What are our cross-products?????

14)1260(5

450

810

Four of the five trees had shed their leaves. If there were 250 treesin the meadow, how many still had their leaves?

Had leaves 1

Shed leaves 4

Total trees 5 250

What are our cross-products?????

5)250(4

200

50

Three of every seven houses on the block have a fence. If there are56 houses in that neighborhood that do not have fences, how many housesare there? How many DO have fences?

No fence

fence 3

total 7

4 56

You could use the scale factor to complete the table. You could alsoset up and solve a proportion. The choice is yours. You must SHOW it.

7(56)4

98

42

The scale factor was 14.

Theater lights………The theater had red lights, yellow lights and blue lights for theirproductions. They had 3 yellow lights, twice as many blue lights, and one less red light than blue lights.

If they wanted to increase their total number of lights to 210, how many of each color would they have?

red 5

yellow 3

blue 6

total 14

14)210(6

21090

45

75

The ratio of crawfish to tadpoles in the creek was 2 to 21. If there were 1932 tadpoles, how many crawfish were there?

What was the total number of these creatures???

crawfish 2

tadpoles 21 1932

total 23

21)1932(2

2116

184

The ratio of residents to visitors in the community pool was 2 to 3. If there were 60 people in the pool, how many were visitors?

residents 2

visitors 3

total 5 60

What are our cross-products?????

5)60(3

36

24

There were 16 red marbles, 24 blue marbles, and 12 yellow marblesin a can. If we double the number of red and yellow marbles, whatis the ratio of all marbles to red?

red 16

blue 24

yellow 12

total 522424

32

8080

80:3240:1620:85:2

What have we done?

• We have used ratios and proportions in another way to solve problems.