australia has rectangular currency notes for 5,10,20,50,100. These notes are all 65mm wide but each note is 7mm longer than the note of the next lower value. What is the difference in area in square millimeters between 10 and 100

• 1365 sq.mm.
  
  If 'x' is the length of note of '5' then,
  Length of the notes of 10,20,50,100 will be (x+7),(x+14),(x+21),(x+28) respectively.
  Difference in Area of notes of 100 & 10 =65[(x+28)-(x+7)]=65*21=1365 sq. mm.
• 10 years agoHelpfull: Yes(1) No(0)