A ferry, when empty , travels twice as fast as when it is full. It travels 20 miles south with a cargo, spends 30 minutes for unloading , and returns to its original port empty in a total of 8 hours , what is the speed of the ferry when it is empty?
A bicycle has two wheels of 120 cm and 40 cm in diameters. when the large wheel makes 10 revolutions , how many revolutions does the small wheel make in that time?
Two numbers A and B are such that the sum of 5% A and 4% of B is two - third of the sum o f 6% A and 8% of B. what is the ratio of A and B.
Baki lives 2 miles west of Raju's house . Rafiq lives 3 miles of Raju's house and 2 miles west o Diba's house. what is the straight-line distance from Baki's house to Diba's house?
On Tuesday, 30 of the students in a class took a test and their average score was 83.5 . On Thursday , the other 5 students took the test, and their average score was 94. what was the average for the entire class?
If the average of 7 , 13 , p , and q is 17 , what is the average of ( p +1) and (q -9) ?
A circular logo is enlarged to fit the lid of a jar. The new diameter is 50 percent larger than the original . By what percentage has the area of the logo increased?
At a particular moment, if the angle between the hour and the minute hand of a clock is 105% what was the time by the clock at that time?
In a college, 45% of the students are boys.If 40% of the boys and 20% of the girls went on a picnic, what percentage on the total students went to the picnic ?
If x = 2y =3z and xyz =36 , what is the value of z?