For this case we have that the complete question is:
There were 20 drinks in a cooler. Joey drank 15% of the drinks. Sandra drank 1/5 of the drinks. Hannah drank 1/4 of the drinks. Tammy drank 30% of the drinks. How many drinks are left in the cooler? a 0 b 2 c 5 d 9
We propose a rule of three:
20 ---------> 100%
x ------------> 15%
Where the variable "x" represents the amount of drinks equivalent to 15%.
[tex]x = \frac {15 * 20} {100}\\x = 3[/tex]
So, Joey drank 3 drinks.
On the other hand, we have that Sandra drank [tex]\frac {1} {5}[/tex]of the drinks:
[tex]20 * \frac {1} {5} = \frac {20} {5} = 4[/tex]
Thus, Sandra drank 4 drinks.
In addition, Hannah drank[tex]\frac {1} {4}[/tex] of the drinks:
[tex]20 * \frac {1} {4} = 5[/tex]
So Hannah drank 5 drinks.
Finally, Tammy drank 30% of the drinks:
20 ---------> 100%
y ------------> 30%
Where the variable "y" represents the amount of drinks equivalent to 30%.
[tex]y = \frac {30 * 20} {100}\\y = 6[/tex]
So Tammy drank 6 drinks.
Adding up we have:
[tex]3 + 4 + 5 + 6 = 18[/tex]
So: [tex]20-18=2[/tex]
Thus, 2 drinks remain in the refrigerator.
Answer:
Option B