Question

In which of the following situations, do the lists of numbers involved form an AP?
If true then enter $1$ and if false then enter $0$The fee charged every month by a school from Classes I to XII, when the monthly fee for Class I is Rs 250, and it increases by Rs 50 for the next higher class.
If true then enter $1$ and if false then enter $0$

Answer 1

The fee charged every month by a school from Classes I $=250$
The fee charged every month by a school from Classes II $=250+50=250+1\times 50=300$
The fee charged every month by a school from Classes III $=250+50+50=250+2\times 50=350$
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.
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The fee charged every month by a school from Classes XII $=250+11\times 50=800$
Therefore list of numbers formed from fee charged is
$250,300,350,...,800$
Clearly it is an AP, because next term is obtained from preceding term by adding a constant $50$.