There are many ways you can write a ratio. They're all basically the same thing, though. 5:9, 5 to 9, and 5/9 (which is a fraction) are all just different ways to write ratios.
Change the fractions so they have common denominators. For example. If adding 4/8 + 2/3, a common denominator of the two could be 24. Change both fractions to have a denominator of 24. To do this:
(4/8)×(3/3)= 12/24
(2/3)×(8/8)=16/24
Now that both fractions have denominators of 24, you can simply add the numerators to get your answer. in this case, it would be 28/24
Given :
p = 0.68
margin of error, E = 0.1
99% confident interval
alpha, α = 1 - 0.99
= 0.01
∴ 
(z-critical value)
Sample size = 
= 144.37
= 145 (rounded off)
Therefore, there are 145 businesses does she need to sample to meet this criteria.
