The speed of a boat in still water is 2 times more than that of the current. If the boat takes 12 hours to cover 144 km upstream, then find the time taken by the boat to cover 480 km downstream.

What will come in place of the question mark (?) in the following series?

5, 6, 14, 45, ?,925

The following numbers form a series. Find the odd one out.

3, 6, 2, 8, 2.4, 9.6

In a school there are 840 students, and the ratio of the number of boys to girls is 5:2. If 120 boys and 180 girls took admission in the school, then find the new ratio of the number of boys to girls in the school.

Ratio of speed of boat in still water and upstream speed of boat is 6:5, respectively. If downstream speed of boat is 17.5 km/h, then find the upstream distance cover by boat in 4 hours.

Marked price of an article, which is sold after 18% discount, is Rs. 12,300. If profit earned on selling the article is Rs. 996, then find the cost price of article.

Three years ago from now, sum of ages of 'P' and 'Q' was 49 years. If ratio of present ages of 'P' and 'Q' is 5:6, respectively, then find the age of 'Q' four years hence from now.

'A' & 'B' started a business with investment of Rs. 5,400 & Rs. 4,500 resp. After 8 months, 'A' decreased his investment by Rs. 900 whereas 'B' increased his investment by Rs. 900. Find the ratio of profit of 'A' to that of 'B' at the end of 12 months.

18 men working 8 hours a day complete a work in 20 days whereas 12 women working 10 hours a day complete the work in 30 days. Find the ratio of efficiency of 6 men and 4 women, respectively.

What will come in place of the question mark (?) in the following series?

293, 420, 547, ?, 801, 928