Answer:
Mark's mass is 26 kg.
Step-by-step explanation:
Average mass of Jeremy, Mark and Zack = 28kg
Average mass of Jeremy and Zack = 29 kg
Let,
Jeremy's mass = x
Mark's mass = y
Zack's mass = z
Average of three of them = [tex]\frac{Jeremy's mass + Mark's + Zack's}{3}[/tex]
28 = [tex]\frac{x+y+z}{3}\\[/tex]
[tex]28*3 = x+y+z\\84 = x+y+z[/tex]
x+y+z = 84 Eqn 1
[tex]29 =\frac{x+z}{2}\\58=x+z\\[/tex]
x+z = 58 Eqn 2
Now putting value of x+z from Eqn 2 in Eqn 1
x + z + y = 84
58 + y = 84
y = 84 - 58
y = 26
Thereofore,
Mark's mass is 26 kg.
