On a wall 78.4cm wide, Peter is going to hang five pictures beside each other, each measuring 12.5 cm wide. He will leave 2.6 cm in between each pair of adjacent pictures. He plans to use two nails to hang each picture. and will center these nails leaving 4.5 cm between each pair. How far, in cm, from the end of the wall (on either side) will the first nail be placed?
