mightymk
In a candy dish the ratio of red to yellow candies is 2:5, the ratio of red to green candies is 3:8, and the ratio of yellow ot blue candies is 9:2.what is the maximum total number of yellow and green candies combined if the maximum combined number of red and blue candies is fewer than 85?
A. 144
B. 189
C. 234
D. 279
E. 309
Since the ratio of red to yellow candies is 2:5 and the ratio of yellow to blue candies is 9:2, we must multiply each ratio by a different constant such that the numbers for yellow candy are the same in each ratio:
Multiplying the first ratio by 9, we see that the ratio of red to yellow candies is 18:45. If we multiply the second ratio by 5, we obtain a ratio of yellow to blue candies of 45:10. Now that the ratio numbers for the yellow candies is the same (45), we can directly relate red to blue candies as a ratio of 18:10, or 9:5.
Thus, we can create the equation:
9x + 5x < 85
13x < 85
x < 6.54
Since x is an integer, the maximum integer value of x is 6. Therefore, we have a maximum of 9(6) = 54 red candies. Since the ratio of red to yellow candies is 2:5 and 2 x 27 = 54, we have a maximum of 5 x 27 = 135 yellow candies. Likewise, since the ratio of red to green candies is 3:8 and 3 x 18 = 54, we have a maximum of 8 x 18 = 144 green candies. Therefore, we have a maximum of 135 + 144 = 279 yellow and green candies.
Answer: D