Question 220880
three unknowns means three equations


"Roger has three times as many apples as Sam" ___ R = 3S


"Sam has twice as many apples as Christi" ___ S = 2C


"Roger has 12 more than both Sam and Christi together" ___ R = S + C + 12


substituting ___ 3S = S + C + 12


substituting ___ 6C = 2C + C + 12 ___ 3C = 12 ___ C = 4


substituting ___ S = 2(4) = 8


substituting ___ R = 3(8) = 24