a shopkeeper earns a profit of rs 1 by selling one pen and incurs a loss of 40 paise per pencil while selling pwncils of her old stock.
1)in a particular month she incurs a loss of rs 5. in this period she sold 45 pens how many pencils did dhe sell in this period?
2)in the next month she earns neither profit nor loss. if she sold 70 pens how many pencils did she sell?
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