Common Ratio Formula
A relation is getting form the comparison of two quantities like in some wisdom is called a common ratio. Common ratio will be show by the terms of fraction, that is, a:b is equal to `a/b` For example 25 is `1/4` of the hundred, Therefore, the ratio of 25 to 100 is `1/4` . We can write it in ratio as 1:4.
Examples for common ratio formula:
Example 1:
If 19 pounds of pizza cost $15, calculate the common ratio for 26 pounds of pizza by using formula.
Solution:
19 pounds of pizza cost is $15 is expressed in common ratio format as 19: 15. This can be written in fraction format as `19/15` . Therefore,
`19/15` = `26/x`
Now we have to do the cross multiplication. Therefore we get
19 `xx` x = 26 `xx` 15
19x = 390
Now we have to divide both sides by 19. Therefore we get
`(19x)/19` = `390/19`
x = 20.53
Therefore, the cost of 26 pounds of pizza is $20.53
Example 2:
If 20 pounds of flowers cost is $16, calculate the common ratio for 27 pounds of flowers by using formula.
Solution:
20 pounds of flowers cost $16 is expressed in common ratio format as 20: 16. This can be written in fraction format as `20/16` . Therefore,
`20/16` = `27/x`
Now we have to do the cross multiplication. Therefore we get
20 `xx` x = 27 `xx` 16
20x = 432
Now we have to divide both sides by 20. Therefore we get
`(20x)/20` = `432/20`
x = 21.6
Therefore, the cost of 27 pounds of flowers is $21.6
Practice problems for common ratio formula:
Problem 1:
If 21 pounds of pizza cost is $17, calculate the common ratio for 28 pounds of pizza by using formula.
Solution: Therefore, the cost of 28 pounds of flowers is $22.67
Problem 2:
If 22 pounds of flowers cost is $18, calculate the common ratio for 29 pounds of flowers by using formula.
Solution: Therefore, the cost of 29 pounds of flowers is $23.72
Examples for common ratio formula:
Example 1:
If 19 pounds of pizza cost $15, calculate the common ratio for 26 pounds of pizza by using formula.
Solution:
19 pounds of pizza cost is $15 is expressed in common ratio format as 19: 15. This can be written in fraction format as `19/15` . Therefore,
`19/15` = `26/x`
Now we have to do the cross multiplication. Therefore we get
19 `xx` x = 26 `xx` 15
19x = 390
Now we have to divide both sides by 19. Therefore we get
`(19x)/19` = `390/19`
x = 20.53
Therefore, the cost of 26 pounds of pizza is $20.53
Example 2:
If 20 pounds of flowers cost is $16, calculate the common ratio for 27 pounds of flowers by using formula.
Solution:
20 pounds of flowers cost $16 is expressed in common ratio format as 20: 16. This can be written in fraction format as `20/16` . Therefore,
`20/16` = `27/x`
Now we have to do the cross multiplication. Therefore we get
20 `xx` x = 27 `xx` 16
20x = 432
Now we have to divide both sides by 20. Therefore we get
`(20x)/20` = `432/20`
x = 21.6
Therefore, the cost of 27 pounds of flowers is $21.6
Practice problems for common ratio formula:
Problem 1:
If 21 pounds of pizza cost is $17, calculate the common ratio for 28 pounds of pizza by using formula.
Solution: Therefore, the cost of 28 pounds of flowers is $22.67
Problem 2:
If 22 pounds of flowers cost is $18, calculate the common ratio for 29 pounds of flowers by using formula.
Solution: Therefore, the cost of 29 pounds of flowers is $23.72