Arun has to take two separate tablets – A and B for 30 days. He has stored 30 quantity of tablet A in a jar and 30 quantity of tablet B in another jar.
Both tablets are identical in appearance, weight, smell and taste. So its impossible to distinguish between A and B.
Every day he opens first jar and puts 1 tablet A in his hand. Then he opens second jar and takes 1 tablet B. He then put both of them in his mouth and swallows. This went on smoothly for 20 days.
On 21st day after taking medicine from both jars he found that he had taken 4 tablets. Help Arun to take proper dosage of medicines for 30 days.
Hint: Only dosage matters not the shape of tablet.
Answer: There are 3 cases here:
All tablets from 1 jar:
Count the remaining tablets in the jar. If any of the jar has 10 tablets, then all the 4 were taken from the other jar. Arun can but the 4 back in the other jar and continue as usual.
2 tablets from each jar:
If both jars contains 8 tablets each then, Arun has 2 A tablets and 2 B tablets. He can carefully split all the 4 tablets into half and keep all left portions together and right portions together. Now the left portion has 1/2 A, 1/2 A, 1/2 B and 1/2 B tablets adding to 1 A tablet and 1 B tablets. So he can take all left portion on 21st day, right portion on 22nd day, then continue as usual.
3 tablets from 1 jar and 1 from another:
If 1 jar contains 7 and other contains 9 tablets, then Arun has taken 3 from 1 jar and 1 from other jar. Here Arun need to take 2 more tablets from the jar containing 9 tablets, then grind all the 6 tablets, mix in properly and then take 1/3rd of the mix on 21st, 22nd and 23rd day.