A single mass m1 = 3.4 kg hangs from a spring in a motionless elevator. The spring is extended x = 14 cm from its unstretched length.

I found the spring constant to be 2.38Nm

but then I come across this question:
a) Now, three masses m1 = 3.4 kg, m2 = 10.2 kg and m3 = 6.8 kg hang from three identical springs in a motionless elevator. The springs all have the same spring constant that you just calculated above.
What is the force the top spring exerts on the top mass?

I tried the answer 33.3 which is wrong because the top mass holds the other two, but just adding the masses and plugging it i

Question

A single mass m1 = 3.4 kg hangs from a spring in a motionless elevator. The spring is extended x = 14 cm from its unstretched length.

I found the spring constant to be 2.38Nm

but then I come across this question:
a) Now, three masses m1 = 3.4 kg, m2 = 10.2 kg and m3 = 6.8 kg hang from three identical springs in a motionless elevator. The springs all have the same spring constant that you just calculated above.
What is the force the top spring exerts on the top mass?

I tried the answer 33.3 which is wrong because the top mass holds the other two, but just adding the masses and plugging it i