Xavier, yaozhou and zara had some beads. xavier and yaozhao had a total of 438 beads. xavier and zara had a total of 204 beads. yaozhao had 3 times as many bead

Xavier = X
Yaozhou = Y
Zara = Z

x+y = 438
x+z = 204 •••••(2)

y = 3z

x+y = 438
x+3z = 438 ••••(1)

x+3z = 438
x+z = 204 (x3)
-------------
x+3z = 438
3x+3z = 612
-------------(dikurang)
-2x = -174
x = -174/-2
x = 87 beads

So, xavier has 87 beads