Sum of first n even numbers = n (n + 1) Required sum = Sum of 30 even numbers from 1 to 60 – sum of 15 even numbers from 1 to 30 = 30 × 31 – 15 × 16 = 930 – 240 = 690
If 10 men can complete a piece of work in 12 days by working 7 hours a day, then in how many days can 14 men do the same work by working 6 hours a day?
A can do (2/5) of a work in 6 days and B can do 30% of the same work in 3 days. They worked together for 4 days. The remaining work was completed by C a...
A and B can together complete a task in 18 hours. After 6 hours A leaves. B takes 36 hours to finish rest of the task. How many hours would A have take...
A thief steals a bike at 12:30p.m. and drives it at 48km/h. But the theft is discovered after half an hour. The bike owner starts to chase him on anoth...
A can complete 40% of a work in 6 days and B can complete 33(1/3)% of the same work in 8 days. They work together for 8 days. C alone completes the rem...
A and B can complete a work together in 36 days. If A alone can complete one-fourth of the work in ‘x’ days and remaining work is completed ...
A and B alone can complete a work in 30 and 60 days, respectively. 50% of the work is completed by C in 6x days, and the remaining work is completed by ...
If 12 persons working 12 hours a day dig 12 meters of a tunnel in 12 days how many men are required to dig additional 4 meter of the tunnel (of the same...
A and B can finish a work working on alternate days in 19 days, when A works on the 1st day. Similarly, they can finish the work working on alternate da...
A motorboat whose speed is 20 km/h in still water takes 30 minutes more to go 24 km upstream than to cover the same distance downstream. If the speed of...
