Wednesday 82634

Two hundred sixteen tickets were sold in the first four days of the week. One-quarter of those tickets were sold on Monday, one-fifth more than on Tuesday. The same number of tickets were sold on Thursday as on Tuesday and Wednesday combined.

How many were sold on Tuesday?
How many were sold on Thursday?

Correct answer:

b =  45
d =  81

Step-by-step explanation:

$$\begin{gathered} a+b+c+d=216 \\ a=216/4=54 \\ a=b+b/5 \\ b=a/(1+1/5)=54/(1+1/5)=45 \end{gathered}$$

$$\begin{gathered} d=b+c \\ a+b+c+(b+c)=216 \\ 54+45+c+(45+c)=216 \\ 2c=72 \\ c=\frac{72}{2}=36 \\ c=36 \\ d=b+c=45+36=81 \end{gathered}$$

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