To the cinema 2

A cinema ticket costs 150 CZK for children and 200 CZK for adults. 100 tickets were sold for the film screening and the cashier collected 16,000 CZK. Calculate:
a. How many children's tickets were sold?
b. How much CZK was collected for the adult ticket?
c. By what percent is the children's ticket cheaper than the adult ticket?

Final Answer:

a =  80
d =  4000 Kc
c =  25 %

Step-by-step explanation:

$$\begin{gathered} 150a+200b=16000 \\ a+b=100 \\ 150\cdot a+200\cdot b=16000 \\ Row2-\frac{1}{150}\cdot Row1\to Row2 \\ -0.33b=-6.67 \\ b=\frac{-6.66666667}{-0.33333333}=20 \\ a=\frac{16000-200b}{150}=\frac{16000-200\cdot 20}{150}=80 \\ a=80 \\ b=20 \end{gathered}$$

$d=200\cdot b=200\cdot 20=4000\text{Kc}$

$c=100\cdot \frac{200-150}{200}=25\%$

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