Actually Welcome to the Concept of the Equilateral Triangles.
Since, we know that, all the sides of a triangle are equal, hence it is a Equilateral triangle.
Equilateral triangle has one all angles equal to 60°.
so, major angle P = 60°
hence, 2x=60°
===> x = 30°
Group A
Money spent by Person 1 = £500
Money spent by Person 2 = £600
Money spent by Person 3 = £900
Money spent by Person 4 = £450
Sum of money spent by group A = £2,450
Average money spent by group A =
⇒ Average money spent by group A = £612.5
Group B
Money spent by Person 1 = £700
Money spent by Person 2 = £500
Money spent by Person 3 = £680
Money spent by Person 4 = £500
Sum of money spent by group B = £2,380
Average money spent by group B =
⇒ Average money spent by group B = £595
Hence, Group B had lower average spend.