A jar full of whisky contains 40% alcohol. A part of this whisky is replaced by another containing 19% alcohol and now the percentage of alcohol becomes 26%. The quantity of whisky replaced is:
In a market survey, 20% opted for product $A$, 60% for $B$, and the rest were uncertain. If the difference between those who opted for $B$ and those uncertain is $720$, how many individuals were surveyed?
The captain of a cricket team of 11 members is 26 years old and the wicket keeper is 3 years older. If the ages of these two are excluded, the average age of the remaining players is one year less than the average age of the whole team. Find the average age of the team.