The average of marks obtained by $150$ candidates in a certain examination is $50$. If the average marks of passed candidates is $55$ and that of the failed candidates is $25$,what is the number of candidates who passed the examination?

There are three baskets of fruits. The $1^{st}$ basket has twice the number of fruits in the $2^{nd}$ basket. The $3^{rd}$ basket has three-fourths of the fruits in the first. The average of the fruits in all the baskets is $30$. What is the number of fruits in the first basket?

Ashish has earned an average of $4200$ dollars for the first eleven months of the year. If he justifies his staying on in the $US$ on the basis of his ability to earn at least $5000$ dollars per month for the entire year,how much should he earn (in dollars) in the last month to achieve his required average for the whole year?

The average salary of all workers in a workshop is $Rs. 12000$. The average salary of $7$ technicians is $Rs. 15000$ and the average salary of the rest is $Rs. 9000$. The total number of workers in the workshop is:

The average revenue of $13$ consecutive years of a company is $Rs. 70$ lakhs. If the average of the first $7$ years is $Rs. 65$ lakhs and that of the last $7$ years is $Rs. 77$ lakhs,find the revenue for the $7^{th}$ year (in $Rs.$ lakhs).

The frequency distribution data is given below. If the average age is $17 \text{ years}$,the value of $m$ is:

Age (in years)	$8, 20, 26, 29$
Number of People	$3, 2, m, 1$