Question
A student's scores in four subjects are in the ratio
3:4:5:6. The student achieved an overall average of 72% on the exam. If the maximum possible score for each subject is the same, in how many subjects did the student exceed 75%?Solution
CORRECT OPTION: d SOLUTION: Let the total maximum marks of each subject = 100 Total maximum marks of all 4 subjects = 400 Total obtained marks = 72% of 400 = 288 Let the marks of the students in each subject be 3x, 4x, 5x and 6x 3x+4x+5x+6x = 288 18x = 288 x = 16 marks in each subject = 3x, 4x, 5x, 6x = 48, 64, 80, 96 in only 2 subjects he scored more than 75%.
If a boat's downstream and upstream speeds are 30 km/hr and 22 km/hr respectively, and it travels (x + y) km upstream in 10 hours when the stream speed ...
Speed of current is equal to 15% of speed of boat in still water. If the boat takes 12 hours to cover 120 km in still water, then find the time taken by...
A boat can cover 150 km in downstream in 15 hours and 130 km in upstream in 13 hours. Find the distance travelled by the boat in still water in 5 hours.
The downstream speed of a boat is 8 km/hr more than its upstream speed and the ratio of the speed of the boat in still water to the speed of the stream ...
A swimmer swims from a point A against a current for 12 minutes and then swims backwards in favour of the current for next 12 minutes and comes to the p...
A man can row at 36 km/hr in still water. In a stream which is flowing at 12 km/hr, it takes him 3 hrs to a place and back. How far is the place?
Motor boat covers a certain distance downstream in 5 hours. It covers the same distance upstream in 7(1/2) hour. If the speed of the water is 4.5 km/hr,...
A boat can travel 36 km downstream in 2 hours and 24 km upstream in 3 hours. Find the speed of the boat in still water and the speed of the stream.
A boat can cover 150 km in downstream in 15 hours and 120 km in upstream in 12 hours. Find the distance travelled by the boat in still water in 5 hours.
Ratio of speed of boat in downstream and speed of stream is 7:3, if speed of current is 9 km/hr, then find distance travelled (in km) upstream in 6 hours.
