A record is made of the emissions from one nucleus during a decay chain.
| Type of emission | Number recorded |
|---|---|
| alpha | 1 |
| beta-minus or beta-plus | 3 |
The record does not show which of the beta emissions were beta-minus and which were beta-plus.
The original nucleus contains 70 protons and 100 neutrons. The final nucleus contains 67 protons.
Calculate the number of beta-minus decays and the number of beta-plus decays. Compare the number of neutrons in the final nucleus with the number in the original nucleus.
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