springs constant help

2 springs are connected in series to a weight, what would be the effect of adding an additional spring in series to the system, in terms of extension and its effect on a "mass vs extension" graph.

Thank you

Adding an extra spring would cause the series to distribute the mass equally on the springs. - Mass/3 should be the amount each spring bears. Each spring should decrease in extension slightly as the third spring will take more of the weight and will distribute it.

No, this is what happens when you add springs in parallel.

In the series case, each spring extends the same amount as if it were on its own. For any load the total extension is 3 times the value for one spring.

So the spring constant decreases? By 3?

& the extension increases by 3?