Mathematics
The speed of a boat in still water is 11 km per hour. It can go 12 km upstream and return downstream to the original point in 2 hours and 45 minutes. Find the speed of stream.
Related Questions
Solve :
13x - 5 < 15x + 4 < 7x + 12, x ∈ R. Represent the solution set on a real number line.
P and Q are points on the sides AB and AC of triangle ABC. If AP = 3 cm, PB = 6 cm, AQ = 4.5 cm and QC = 9 cm, show that BC = 3 × PQ.
The marks obtained (out of 100) by 400 students in an examination are given below :
Marks No. of students 0-10 10 10-20 20 20-30 22 30-40 40 40-50 54 50-60 76 60-70 80 70-80 58 80-90 28 90-100 12 Using a graph paper, draw an ogive for the above distribution. Use your graph to estimate :
(i) the median marks.
(ii) the number of students who obtained more than 80% marks in the examination.
(iii) the number of students who did not pass, if the pass percentage was 35.