Question 919098
Write an equation for each statement
:
"The ages of Grandad, Uncle John and Tom add up to 105 years."
g + j + t = 105
 "Grandad is twice as old as Uncle John,"
g = 2j
 "and Uncle John is twice as old as Tom."
j = 2t
divide both sides by
t = .5j
:
Replace g and t in the 1st equation
2j + j + .5j = 105
3.5j = 105
j = 105/3.5
j = 30 yr is John;s age
:
You should be able to find the other ages, ensure that they add up to 105 

 Grandad is how old? Uncle John is how old? Tom is how old?