Age 5: Malawi (Casino)
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Source & more detail information: https://en.wikipedia.org/wiki/Gambling_age#cite_note-27
15 years and above seems to be a reasonable age to set. During this time, they at least learn to take their own decision and starts to understand the "financial" aspects of the life/world.
How much more no playing, im not really sure if this one is a legit info or just some sort of typo.When it comes to restrictions then it should be standardized on age 18 but due too high-technology nowadays
its really hard to suppress for young minds to get involved on early age without being detected.
I cant be sure that these laws or restrictions is being followed well on said countries.