An empty cart, tied between two ideal springs, oscillates with ω = 10.1 rad/s.A load is placed in the cart, making the total mass 3.9 times what it was before. What is the new value of ω?

Question

rad/s

This is how I did it, but its wrong
3.9/3=1.3 then 1.3x10.1=13.13 rad/s
I don't know what I am doing wrong.

Answer 1

ω1 =sqrt (k/m)
ω2 =sqrt (k/(3.9•m))
ω2/ ω1 = sqrt(k•m/(3.9•m•k)=0.506
ω2 = 0.506•ω1=5.11 rad/s