Answer:
Xavier has 136 beads, Yaozhou has 204 beads and Zara has 68 beads.
Explanation:
Let the number of beads that Xavier has be x.
Let the number of beads that Yaozhou has be y.
Let the number of beads that Zara has be z.
The total number of beads they have altogether is 438. This means that:
x + y + z = 438 _______(1)
Xavier and Zara have a total of 204 beads. This means that:
x + z = 204
=> x = 204 - z _______(2)
Yaozhou has 3 times as many beads as Zara. This means that:
y = 3z _________________(3)
Put (2) and (3) in (1):
204 - z + 3z + z = 408
3z = 408 - 204 = 204
z = 204/3 = 68
From (2):
x = 204 - 68 = 136
From (3):
y = 3 * 68 = 204
Therefore, Xavier has 136 beads, Yaozhou has 204 beads and Zara has 68 beads.