MO Z7–I–3 2017

A zoological garden offered school groups an advantageous admission: every fifth pupil gets a ticket free of charge. The teacher of 6.A calculated that if he buys admission for the children from his class, he will save for four tickets and will pay 19.95 €. The teacher of 6.B suggested to him
to buy tickets for the children of both classes at once, and thus they will pay 44.10 €. How many children from 6.A and how many children from 6.B went to the zoo? (The price of the ticket in cents is an integer.)

Final Answer:

a =  23
b =  29

Step-by-step explanation:

$$\begin{gathered} b_1=4410/c=4410/105=42 \\ {b}_2=\lfloor b_1/4\cdot 5\rfloor =\lfloor 42/4\cdot 5\rfloor =52 \\ b=b_2-a=52-23=29 \end{gathered}$$

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