Solve a Word Problem: Find the Number of Marbles Jack Has

[kyphysics]

Homework Statement

Jack has three times as many marbles as Chris. Chris has 2/3 as many marbles as Amy. Amy has 27 marbles. How many marbles does Jack have?

Homework Equations

The Attempt at a Solution

Jack = 3x
Chris = 2/3(27)

3x = 2/3(27)

This this equation above correct for representing this word problem?

 

[DaveC426913]

This this equation above correct for representing this word problem?

No, but you're almost there.

Try solving for x, and see what you get for Jack, Chris and Amy. You'll find Jack's is not 3x Chris'.

Use Chris as the common variable, since he's compared to both Jack and Amy:
Chris = x
Jack = ?x
Amy = ?x

 

[Mark44]

Use Chris as the common variable, since he's compared to both Jack and Amy.

Chris = x
Jack = ?x
Amy = ?x

This naming scheme might be a little confusing, as you will get (or should get) numbers for Chris, Jack, and Amy, and there's no indication that you really mean how many marbles each of them has. Instead of using their names, I would do this:

Let C = # of marbles Chris has
Let J = # of marbles Jack has
Let A = # of marbles Amy has

Jack has three times as many marbles as Chris. Chris has 2/3 as many marbles as Amy. Amy has 27 marbles. How many marbles does Jack have?

Use the first two sentences above to get relationships between C, J,and A.