Subscription 12191

They sell three prepaid coupons for bus travel - for a month for 500 CZK, a quarter for 1200 CZK, or a whole year for 4200 CZK. Mom rides the bus all year round. Which subscription will be the cheapest for her, and by how much?

Correct answer:

a =  500 Kc/m
b =  400 Kc/m
c =  350 Kc/m
x =  150 Kc/m

Step-by-step explanation:

$a=500=500\text{Kc/m}$

$b=1200/3=400\text{Kc/m}$

$c=4200/12=350\text{Kc/m}$

$$\begin{gathered} c<b<a \\ x=a-c=500-350=150\text{Kc/m} \end{gathered}$$

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