Question 1068108
{{{L}}}= length of the original piece of fretboard
{{{W}}}= width of the original piece of cardboard
{{{W*L}}}= area of the original piece of cardboard
{{{(3/4)*L}}}= new length
{{{(4/5)*W}}}= new width
The new area is
{{{(3/4)*(4/5)*L*W=(3/5)*(W*L)=(60/100)*(W*L)=highlight("60%")*(W*L)}}}