The ratio of red collars to black collars sold at one store is 9 to 10. In one month 30 black collars are sold. Is 57 a reasonable number for the total number of red and black collars sold that month? Explain your reasoning.
Yes because if the ratio is 9:10, then the new ratio would be ?:30. Since 10 was multiplied by 3, 9 should also be multiplied by 3, which equals 27. 30+27=57 so yes it is a reasonable number for the total
