2 pentagrams =4 triangles

8 triangles =72

1 triangle =9

1 pentagram =9+9= 18

2. Circle =3 squares

2 circles =3+3=6 squares ×

9 diamonds =90

1 square =90÷9= 10

Circle =10+10+10 = 30.

3, 43+48+55= 146=2 circles +2 triangles +2 squares.

1 circle+1 triangle+1 square = 146 ÷2=73

73-43=30 (triangle)

73-48=25 (i.e. circle)

73-55= 18 (square)