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## 'CD Heaven' printed from http://nrich.maths.org/

All CD Heaven stores were given the same number of a popular CD
to sell for $£24$.

In their two week sale each store reduces the price of the CD by
$25\%$ and any further reductions are then left to the discretion
of the store managers.

Towards the end of the two week sale one store still had $30$
CDs left and the manager decided to try to clear the remainder by
reducing the price by a further $1/3$ but still did not manage to
sell them all. The total sales for the CDs was $£2010$.
If the store had managed to sell all its CDs by the end of the two
week sale period it would have received $£2370$.

Another store sold the same number of CDs before and during the
first two weeks of the sale as the first store but in reverse order
(the number they sold for $£24$ was the same as the
number sold in the two weeks of the sale by the first store and
vice versa). At the end of the two weeks the shop manager decided
to reduce the price of the CDs by a further $50\%$ and managed to
sell all the remaining $30$ CDs making her total sales
$£2010$.

How many CDs did the first store sell at each price?