John bought $10$ pencils and notebooks in total for £$44$. Each pencil cost £$$2$$. Each notebook costs £$$8$$. How many notebooks did John buy? 
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If all were pencils,  $10\times 2= 20$  the total cost would be £$$20$$.  $44- 20=24$  The difference is £$$24$$.  $8-2=6$  $24\div 6=4$  John bought $4$ notebooks. 