Time & Work, Chain Rule

A can finish a work in 5 days and B takes 4 days to do the same work. If the work is increased 8 times, how many days will it take for both of them to finish the work if they work together?

The cost of renting a small bus for a trip was Taka X which was to be shared equally by 16 persons. Actually 10 persons availed the trip. How much more Taka will be the cost per person?

A tap can fill a tank in 6 hours. After half the tank is filled another similar tap is opened. What is the total time taken to fill the tank completely?

Mr. Jamal employed 50 workers to finish a work within 30 days. After 20 days he found out that only 50% work had been completed. How many additional workers would be needed to finish the task in scheduled time?

A and B together can do a piece of work in 40 days. A having worked for 20 days, B finishes the remaining work alone in 60 days. In How many days shall B finish the whole work alone?

A certain machine produces 1,000 units of product P per hour. Working continuously at this constant rate, this machine will produce how many units of product P in 7 days?

The price of a pen is 25% more than the price of a book. The price of a pen holder is 50% more than the price of the book. How much is the price of the pen holder more than the price of the pen?

4 men and 6 women can complete a work in 8 days, while 3 men and 7 women can complete it in 10 days. In how many days will 10 women complete it?

A mixture of 20kg of spirit and water contains 10% water. How much water must be added to this mixture to raise the percentage of water to 25%?

A person travels a certain distance at 3 km/hr and reaches 15 min late. If he travels at 4 km/hr, he reaches 15 min earlier. The distance he has to travel is -

It takes 5 hours to fill a container using machine A. The same container can be filled using machine B in 10 hours. When the container is full, Machine C can fully empty the container in 20 hours. If all three machines start working on the same empty container how long will it take for the container to be completely filled,

12 students working for 5 hours a day can solve a certain number of problems in 8 days. How many students are needed to solve five times the original number of problems, if they work at 4 hours a day for 15 days? 

A wheel rotates 10 times per minute and moves 20 m during each rotation. How many meters does the wheel move in 1 hour?

A man rowed 3 miles upstream in 90 minutes. If the river flowed with a current of 2 miles per hour, how long did the man's return trip take?

If three boys can paint a wall in 2 days, what part of the job can be completed by two boys in 1 day?

10 cats caught 10 rats in 10 seconds. How many cats are required to catch 100 rats in 100 seconds?

৩০ × ১৬ ফুটের একটি মেঝে মেরামত করতে ২৪৯৬ টাকা ব্যয় হল। প্রতি বর্গফুটে ব্যয় কত টাকা?

A man's regular pay is Taka 30 per hour up to 40 hours. Overtime is twice the payment for regular time. If he was paid Taka 1680, how many hours of overtime did he work?

Mr. Power attends to, on the average, 12 TV service calls per day. Mr. Fixit attends to, on the average, 16 service calls per day. Mr. Power's average charge is 3/2 as much as that Mr. Fixit, who earns Tk. 7200 per month. The monthly earnings of Mr. Power, in Taka, is-

Machine A produces bolts at a uniform rate of 120 every 40 seconds and Machine B produce bolts at a uniform rate of 100 every 20 seconds. If the two machines run simultaneously, how many seconds will it take for them to produce a total of 200 bolts?