Model Ratios
Writing Equivalent Ratios
Are the ratios equivalent?
Solve Equivalent Ratios
Word Problems
100
Write a ratio of yellow to red circles "3 ways":
5/3, 5:3, 5 to 3
***Yellow comes before the word "to" so that number must be first
100
Write 3 more Equivalent Ratios:
1/4
2/8, 3/12, 4/16
100
Are the Ratios Equivalent?
Show Evidence and write Yes or No.
Rewrite as fractions with a top and bottom on your paper to make it easier.
2/4 = 4/5
2 x 2 = 4
4 x 2 not equal to 5
No!
Butterfly Method: 5x2 = 10 4x4=16 NO!
100
Solve for x to make the Ratios Equivalent:
x/5 = 8/10
5 x 2 = 10
"4" x 2 = 8
x = 4
OR Butterfly Method:
8x5=40/10=4
100
A recipe requires 2 cups of milk for every 3 cups of flour. If you use 8 cups of milk, how many cups of flour do you need?
2 x 4 = 8 so...
3 x 4 = 12
12 cups of flour
OR Butterfly Method:
8x3= 24 24/2 = 12 cups of flour
200
Write a ratio of red to blue circles "3 ways":
5/6, 5:6, 5 to 6
***Red comes before the word "to" so that number must be first
200
Write 3 more Equivalent Ratios:
2/9
4/18, 6/27, 8/36
200
Are the Ratios Equivalent?
Show Evidence and write Yes or No.
Rewrite as fractions with a top and bottom on your paper to make it easier.
5/10 = 3/6
Both are = to 1/2
5 is half of 10 and 3 is half of 6
Yes!
Also, Butterfly Method: 6x5=30 and 3x10=30 YES
200
Solve for x to make the Ratios Equivalent:
3/9 = 9/x
3 x 3 = 9
9 x 3 = 27
x = 27
OR Butterfly Method:
9x9=81 81/3=27
200
For every $5 Carl spends on movies, he spends $15 on video games. Last month, he spent $45 on video games. How much did he spend on movies?
Ratio is 5:15
double: 10:30 (x2)
triple: 15:45 (x3)
$15 on movies
300
There are 5 dogs and 3 cats. What is the ratio of cats to dogs?
3:5
***cats comes before the word "to" so that number must be first
300
Write 3 more Equivalent Ratios:
9/13
18/26, 27/39, 36/52
300
Are the Ratios Equivalent?
Show Evidence and write Yes or No.
Rewrite as fractions with a top and bottom on your paper to make it easier.
8/10 = 16/18
8 x 2 = 16
10 x 2 not equal to 18
No!
Also, BUTTERFLY METHOD: 18x8 =144 10x16=160
300
Solve for x to make the Ratios Equivalent:
7/14 = 21/x
7 x 3 = 21
14 x 3 = 42
x = 42
OR Butterfly Method:
14x21= 294 294 /7 =42
300
Keely went for a long swim. If she swam 12 km in 3 hours, how far would she swim in 6 hours?
original ratio is 12:3
double ratio: 24:6 (x2)
24km
400
There are 10 white marbles and 3 blue marbles. What is the ratio of blue marbles to total marbles?
3:13
***Blue comes before the word "to" so that number must be first
400
***DAILY DOUBLE***
1 Minute Timed
Write 7 more Equivalent Ratios:
12/16
400
Are the Ratios Equivalent?
Show Evidence and write Yes or No.
Rewrite as fractions with a top and bottom on your paper to make it easier.
3/9 = 1/3
3 divided by 3 = 1
9 divided by 3 = 3
Yes!
Also, BUTTRFLY METHOD: 3x3=9 and 1x9=9 YES
400
Solve for x to make the Ratios Equivalent:
2/10 = x/80
10 x 8 = 80
2 x 8 = 16
x = 16
OR Butterfly Method:
2x80=160 160/10=16
400
The ratio of students who like apple juice to grape juice is 4:3. If 30 kids in the class like grape juice, how many kids like apple juice?
original ratio is 4:3
(x10) __ : 30 (x10)
40 kids like apple juice
OR Butterfly Method:
4x30= 120 120/3 = 40 kids like apple juice
500
There are 2 red blocks, 3 orange blocks, and 4 black blocks. What is the ratio of black blocks to total blocks?
4:9
***Black comes before the word "to" so that number must be first
500
Write 3 more Equivalent Ratios:
24/36
12/18, 6/9, 2/3, 8/12, 4/6,
500
Are the Ratios Equivalent?
Show Evidence and write Yes or No.
Rewrite as fractions with a top and bottom on your paper to make it easier.
10/15 = 4/6
Butterfly Method:
10x6=60 and 4x15=60
Yes!
500
Solve for x to make the Ratios Equivalent:
18/40 = 9/x
18 divided by 2 = 9
40 divided by 2 = 20
x = 20
OR Butterfly Method:
40x9=360 360/18=20
500
The ratio of boys to girls is 5 to 4?
If there are 20 girls, how many boys are there?
4 x 5 = 20 girls
5 x 5 = 25 boys
25 boys
OR Butterfly Method
5x20=100 100/4= 25 boys