Rita + Lamar + Jose = 54
(x+10) + x + 2*(x+10) = 54
Simplify and solve
4x + 30 = 54
4x = 54 - 30 = 24
x = 24/4 = 6.
ANSWER. Lamar sent 6; Rita sent x+10 = 16; Jose sent 2*16 = 32.
CHECK. 6 + 16 + 32 = 54. ! Correct !