A. 1/6, 4/20
B. 7/9, 28/36
C. 14/18, 21/27
A. 1/6, 4/20
B. 7/9, 28/36
C. 14/18, 21/27
D. 30/80, 6/18
B. 7/9, 28/36
C. 14/18, 21/27
Example: 25/45, 15/27 Form a proportion.
First, find the GCF (Greatest Common Factor) of 25 and 45.
25: 1,2,4, (5) ,10,20,25,50,100
45: 1,3, (5) ,9,15,45.
The GCF for 25 and 45 is 5.
Divide 5 by the numerator and denominator:
25÷5= 5
45÷5= 9.
So, 25/45=5/9.
Now for 15/27. Find the GCF for the numerator and denominator:
15: 1, (3) ,5,15
27: 1, (3) ,9,27
The GCF for 15 and 27 is 3.
Divided the numerator and denominator by 3
15÷3=5
27÷3=9.
15/27=5/9.
So, 25/45 and 15/27 form a proportion. Hope This Helped!
(Sorry if this is a lot of writing. Just trying to help give an example for the future)
Let's go through each option:
A. 1/6, 4/20
To compare these ratios, we can cross-multiply.
1 x 20 = 6 x 4
20 = 24
Since the cross-products are not equal, this pair of ratios does not form a proportion.
B. 7/9, 28/36
Again, let's cross-multiply to compare these ratios.
7 x 36 = 9 x 28
252 = 252
Since the cross-products are equal, this pair of ratios forms a proportion.
C. 14/18, 21/27
Cross-multiplying, we have:
14 x 27 = 18 x 21
378 = 378
Once again, the cross-products are equal, so this pair of ratios forms a proportion.
D. 30/80, 6/18
Cross-multiplying:
30 x 18 = 80 x 6
540 = 480
Since the cross-products are not equal, this pair of ratios does not form a proportion.
Therefore, the pairs of ratios that form a proportion are:
B. 7/9, 28/36
C. 14/18, 21/27