Question

Lucy, Sam, and Bob served a total of 72 orders Monday at the school cafeteria. Bob served 3 times as many orders as Lucy. Lucy served 8 more orders than Sam. How many orders did they each serve?

Answer 1

let

x-------> the number of Lucy's orders

y-------> the number of Sam's orders

z-------> the number of Bob's orders

we know that

$x+y+z=72$----> equation A

$z=3x$-----> equation B

$x=8+y-----> y=x-8$ -----> equation C

substitute equation B and C in equation A

$x+(x-8)+3x=72\\ 5x=72+8\\ 5x=80\\x=16$

find z

$z=3*16=48$

find y

$y=x-8------> y=16-8=8$

therefore

the answer is

the number of Lucy's orders is $16$

the number of Sam's orders is $8$

the number of Bob's orders is $48$