a comparison of 2 JavaScript Nuclear Decay HTML5 simulation

a comparison of 2 JavaScript Nuclear Decay HTML5 simulation

1. http://www.opensourcephysics.org/items/detail.cfm?ID=13978&S=7
2. http://iwant2study.org/ospsg/index.php/interactive-resources/physics/06-quantum-physics/02-nuclear/315-decaychangenwee

to check, use the fact that 

The decay constant is the fraction of the number of atoms that decay in 1 second. It is the constant λ in the decay equation: dN/dt = -λN The - sign indicates decay, dN/dt is the number of decays per second (also known as 'Activity') and N is the number of atoms present.

 assuming N = 1600, λ or k = 1, or p = 0.1000,

the following screenshots suggests both simulation are consistent!

assuming N = 1600, λ or k = 1, or p = 0.1000

assuming N = 1600, λ or k = 1, or p = 0.1000