x+( 1+2/5)x+[( 1-4/7)( 1+2/5)]x = 450
x+7/5x+[3/7x7/5]x=450
x+7/5x+3/5x=450
( 1+7/5+3/5)x=450
3x=450
x = 450 \3
x= 150
150x (1+2/5) = 210 (pieces)
2 10x( 1-4/7)=90 (piece)
A: There are 90 red lanterns, 2 yellow lanterns10 and blue lanterns 150.